Health Definitions

An extremely rare condition in which a female has two extra X chromosomes.

An enlarged area in the lower part of the aorta, the body's main artery.

Bloating and swelling in the belly area.

Excess weight that develops over time around the center of the body. Abdominal fat is also called visceral fat.

Pain from inside the belly or from the belly's outer muscle wall, ranging from mild and temporary to severe and needing emergency care.

An abrasion is an injury caused by something that rubs or scrapes against the skin or tissue.

A pocket of pus that collects under the skin or in deeper spaces inside the body.

A skin condition that causes dark, velvety patches in body folds and creases.

A rare condition making it difficult for food and liquid to pass into the stomach.

An injury of the Achilles tendon, which joins the calf muscles to the heel bone.

A partial or complete tear of the tendon just above the heel. The injury makes it hard to raise the foot or walk properly.

The most common type of short-limbed dwarfism.

A buildup of acid in the body.

A skin condition that occurs when hair follicles plug with oil and dead skin cells.

A condition in adults in which the pituitary gland makes too much growth hormone.

A rough, scaly patch on the skin caused by years of sun exposure.

Any condition related to sudden, reduced blood flow to the heart.

A type of cancer of the blood and bone marrow that affects white blood cells.

A type of cancer of the blood and bone marrow that affects mature blood cell growth.

Sudden inflammation in the pancreas.

A condition in which the kidneys suddenly lose their ability to filter waste products from blood.

Condition in which fluid collects in the lungs' air sacs, depriving organs of oxygen.

An illness that happens when the body doesn't make enough of certain hormones.

Swelling of an infection-fighting node, called a lymph node.

A form of cancer that starts in the cells that line certain organs, called glandular cells.

A noncancerous tumor occurring in glandular tissue.

A condition in which the tissue that lines the uterus grows into the muscular wall of the uterus.

A condition involving stiffness and pain in the shoulder joint. Also known as frozen shoulder.

A type of stress-related mental condition brought on by a life change.

A term for a broad group of symptoms such as body aches and tiredness.

A condition where the adrenal glands don't make enough of certain hormones.

A genetic condition that damages the membrane surrounding the brain nerve cells.

A mental health condition exhibited by difficulty maintaining attention.

A disease caused by infection with a parasite spread through a tsetse fly bite.

A type of behavior intending to cause physical or mental harm.

Loss of the ability to identify objects or people.

Fear of places and situations that might cause panic, helplessness, or embarrassment.

A feeling of muscle quivering, restlessness, and inability to sit still, sometimes a side effect of antipsychotic or antidepressant medication.

A group of inherited disorders characterized by little or no melanin production.

A pattern of drinking that interferes with day-to-day activities.

A disturbance in behavior or mental acuity during or after alcohol consumption.

Symptoms that occur after stopping heavy drinking of alcohol.

A chronic disease including uncontrolled drinking and preoccupation with alcohol.

An allergic response causing itchy, watery eyes, sneezing and other coldlike symptoms.

Swelling and irritation of the spaces inside the nose and head, also known as sinuses, due to allergies.

Hair loss from the scalp or body that can occur in people of any age and gender.

Sudden hair loss that starts with 1 or more round bald patches that may overlap.

Feeling sick from lower oxygen levels after arriving at a high altitude.

A painful dental condition occurring after an adult tooth is removed.

A progressive disease that destroys memory and other important mental functions.

A parasitic infection of the colon with the amoeba Entamoeba histolytica.

Not having monthly menstrual periods.

Inability to remember events for a period of time, often due to brain injury, illness, or the effects of drugs or alcohol.

The buildup of amyloid proteins in the heart, kidneys, liver or other organs.

A nervous system disease that weakens muscles and impacts physical function.

A type of cancer that occurs in the anal canal, a short tube at the end of the rectum.

A small tear in the lining of the anus.

An infection between the skin and the anus.

A severe, potentially life-threatening allergic reaction.

General swelling throughout the body.

Hair loss from the scalp, causing baldness.

Hormone changes in men that are related to aging.

A condition in which the blood doesn't have enough healthy red blood cells and hemoglobin.

Low red blood cells caused by certain chronic diseases.

An underdeveloped brain and an incomplete skull.

One or more missing or extra chromosomes.

A ballooning and weakened area in an artery.

A genetic disorder causing developmental disabilities and nerve-related symptoms.

An intense negative emotion ranging from mild irritation to rage.

A type of chest pain caused by reduced blood flow to the heart.

Painless swelling under the skin, triggered by an allergy to animal dander, pollen, drugs, venom, food, or medicine.

Inflammation and small tears in one or both corners of the mouth.

An inability to experience pleasure.

Physical discomfort in the ankle area, often including the joint or the tendon that connects the lower leg to the heel, known as the Achilles tendon.

A condition that restricts the tongue's range of motion.

An inflammatory disease that fuses spinal vertebrae together.

An eating disorder causing people to obsess about weight and what they eat.

A torn anterior cruciate ligament in the knee.

A rare but serious illness that spreads through sick animals or tainted animal products.

A condition in which the immune system mistakenly creates antibodies that attack tissues in the body.

A dysfunction of a person's ways of thinking, perceiving situations, and relating to others.

A chronic mental condition that affects thinking, perceiving, and relating to others.

Intense, excessive, and persistent worry and fear about everyday situations. Fast heart rate, rapid breathing, sweating, and feeling tired may occur.

A mental condition in which excessive, ongoing worry interferes with regular activities.

A tear in the inner layer of the body's main artery, called the aorta.

Narrowing of the valve between the lower left heart chamber and the body's main artery.

Feeling indifferent or lacking emotion, often a sign of depression or misuse of alcohol or drugs.

A language disorder that affects a person's ability to communicate.

A rare and serious condition in which the body stops making enough new blood cells.

A condition in which the appendix becomes inflamed and filled with pus, causing pain.

Cancer of the finger-shaped pouch attached to the colon, called the appendix.

Not feeling hungry nor wanting to eat.

Inability to perform a movement or task when asked despite having the desire and physical capability to carry it out.

Difficulty with skilled movements even when a person has the ability and desire to do them.

Physical discomfort in any part of the arm.

A condition in which brain tissue extends into the spinal canal, present at birth.

An abnormal connection between arteries and veins, usually in the brain or spine.

Swelling and tenderness in one or more joints, causing joint pain or stiffness that often gets worse with age.

Any disease of the joints.

Abdominal swelling caused by accumulation of fluid, most often related to liver disease.

Lack of oxygen to the brain.

A lung infection caused by unintentional inhalation of food, drink, vomit, or saliva.

Eyestrain, or eye fatigue.

A condition in which a person's airways narrow, swell and produce extra mucus.

An imperfection in the eye's curvature.

Showing no symptoms of a medical condition.

Impaired balance or coordination, can be due to damage to brain, nerves, or muscles.

Complete or partial collapse of a lung or a section (lobe) of a lung.

A buildup of fats, cholesterol and other substances in an artery and on the artery walls. Also called plaque.

The buildup of fats, cholesterol and other substances in and on the artery walls.

A condition that causes dry, itchy, and inflamed skin. It's also called eczema.

An irregular, often rapid heart rate that commonly causes poor blood flow.

A heart rhythm disorder in which the heart's upper chambers beat too quickly. Also called an arrhythmia.

A hole in the wall between the heart's upper chambers that's present at birth.

Wasting or degeneration of cells, tissues or organs, caused by a number of conditions.

A condition marked by hyperactivity, impulsiveness, and trouble keeping attention.

A chronic condition including attention difficulty, hyperactivity, and impulsiveness.

A lung infection (pneumonia) with atypical symptoms.

A condition that makes it hard to understand speech.

Symptoms or sensations, such as flashing lights or zigzag lines, which typically precede migraine headache, seizure, or other neurological events.

A serious developmental disorder that impairs the ability to communicate and interact.

A disorder that happens when the immune system attacks the thyroid gland.

The death of bone tissue due to a lack of blood supply. Avascular necrosis also is known as osteonecrosis.

A lack of the recommended blood levels of one or more essential vitamins.

A disorder characterized by social discomfort and avoidance of interpersonal contact.

An injury in which body tissue is ripped or torn away.

A condition in which the body doesn't make sperm.

Elevated levels of certain waste products in the blood.

Small bumps that appear on a baby's cheeks, nose, and forehead.

When a well-fed, healthy baby cries long, hard and loud for no known reason at the same time every day.

Physical discomfort occurring anywhere on the spine or back, ranging from mild to disabling.

A painful infection in a joint.

A condition caused by too much of certain bacteria in the vagina.

A fluid-filled cyst behind the knee.

Inflammation of the foreskin and head of the penis.

Damage to the lower part of the tube that connects the mouth and stomach, called the esophagus.

A small fluid-filled sac near the opening of the vagina.

A type of skin cancer that begins in the basal cells.

Bedbug infestation definition

An injury caused by a bee's venom.

A rare disorder causing swelling, also called inflammation, in blood vessels.

Sudden weakness in the muscles on 1 side of the face.

A common reason for a sudden feeling of spinning or of the world spinning.

Linked to aging, this condition causes the prostate gland to get bigger and cause trouble with urinating.

A condition in which the body doesn't have enough vitamin B-1, also called thiamin.

A type of blood condition passed through families.

When the aortic valve has two flaps instead of three.

Pain that occurs when a gallstone is being passed and is blocking a bile duct, typically comes and goes in a fairly regular pattern.

Frequently consuming unusually large amounts of food in one sitting and feeling that eating behavior is out of control.

A mental health condition that causes extreme mood swings, including emotional highs (mania or hypomania) and lows (depression).

A condition in children marked by intense mood swings.

A mental health condition that causes mood swings, including emotional highs called hypomania and lows called depression.

An infection of the nose, throat and lungs caused by a virus. Bird flu also is called avian flu or avian influenza.

An area of skin that differs from the surrounding skin. It's sometimes present when a baby is born or develops soon after.

A condition caused by bleeding under the skin around the eye, often resulting from an injury.

A temporary condition in which the tongue appears dark and furry.

An open pore clogged with oil, which has turned brown when exposed to the air.

Temporary loss of vision and consciousness.

Cancer that begins in the bladder.

The release of blood from a broken blood vessel, either inside or outside the body.

Inflamed, irritated gums that bleed easily.

Swelling and irritation of the eyelid that affects the eyelashes or tear production.

Occurs when a gestational sac develops without an embryo.

Complete or partial loss of vision.

An area of skin covered by a raised, fluid-filled bubble.

A buildup of gas in the stomach and intestines.

A bump on the skin that's filled with blood.

Blood can appear with bowel movements because of hard stools, constipation, hemorrhoids, digestive conditions or colon cancer.

Any disease that spreads through contact with human blood.

Blue-red marks on a baby's skin that can be caused by blood disorders, a tumor or an infection that spreads to the baby before birth.

Decreased clarity or sharpness in vision.

A mental illness involving obsessive focus on a perceived flaw in appearance.

A contagious, itchy infestation caused by insects.

Odor caused by the mix of sweat and bacteria on the skin.

Any condition or disease that affects the bones.

A complete or partial break in a bone.

When the body doesn't replace bone as fast as it breaks bone down.

A condition that occurs when cancer cells spread from their original site to a bone.

A bony growth that forms on the edge of a bone.

A growth of cells that starts in a bone. Bone tumors may be cancer or not cancer.

A mental disorder marked by emotional instability and severely distorted self-image.

The state of feeling disinterested in one's surroundings, having nothing to do, or feeling that life is dull.

A rare condition caused by the toxin that Clostridium botulinum bacteria produce during infection.

A brain disorder in adult cattle that may be spread to humans through diseased meat.

A slowed heartbeat. The heart beats less than 60 times a minute.

The destruction or deterioration of brain cells.

A condition in which there's no measurable activity in the brain and brainstem.

An emergency condition in which a ruptured blood vessel causes bleeding in the brain.

A cancerous or noncancerous growth of cells in or near the brain.

A cancer that forms in the cells of the breasts.

A fluid-filled sac in the breast that most often isn't cancer.

A growth that forms within the breast tissue.

Various types of discomfort in the breast tissue, often due to a condition that is not breast cancer.

A break in the bone connecting the breastbone and shoulder. This also is known as a clavicle fracture.

A broken bone in the nose. This is also called a nasal fracture.

A condition in which the lungs' airways become damaged, making it hard to clear mucus.

An inflammatory bronchial reaction in young children and infants.

Inflammation of the lining of bronchial tubes, which carry air to and from the lungs.

An illness caused by infection with bacteria and spread from animals to people, mostly through raw dairy products.

A rare heart rhythm disorder that can cause dangerously fast irregular heartbeats.

Blood or bleeding under the skin due to trauma of any kind; typically black and blue at first, with color changes as the bruise heals.

Grinding, clenching, or gnashing of the teeth.

A rare but serious infection caused by bacteria found in small animals and their fleas.

A serious eating disorder marked by binging, followed by methods to avoid weight gain.

A rare skin condition causing large, fluid-filled blisters.

A bony bump that forms on the joint at the base of the big toe.

A fast-growing cancer of the body's germ- and disease-fighting system, also called the lymphatic system.

Damage to the skin or deeper tissues caused by sun, fire, electricity, or chemicals.

The sensation of painful, burning feet.

Ongoing or recurrent burning in the mouth with no obvious cause.

Painful swelling of the fluid-filled pads, called bursae, that act as cushions at the joints.

A bacterial infection of the skin and soft tissue.

A general state of ill health involving great weight loss and muscle loss.

Thickened layers of skin, often on the hands or feet.

A fungal infection typically on the skin or mucous membranes caused by candida.

A small, shallow sore inside the mouth or at the base of the gums.

An illness caused by breathing in too much of this deadly gas.

A group of pus-filled bumps forming a connected area of infection under the skin.

A slow-growing cancer that can start in different places in the body.

A slow-growing cancer that can start in different places in the body.

A cancer developing from cells that line the skin or inner organs, called epithelial cells.

Sudden, unexpected loss of heart function, breathing, and consciousness.

Improper beating of the heart. The heartbeat may be too fast, too slow or chaotic.

Compression of the heart caused by fluid collecting in the sac surrounding the heart.

A life-threatening condition in which the heart suddenly can't pump enough blood.

An enlarged heart, which is a symptom of another condition, not a disease.

A disease of the heart muscle that makes it harder for the heart to pump blood to the rest of the body.

A numbness and tingling in the hand and arm caused by a pinched nerve in the wrist.

An illness also called cat scratch disease that is caused by germs that spread through an infected cat's bites or licks.

Clouding of the normally clear lens of the eye.

A buildup of mucus in the nose, head and throat.

A group of movement abnormalities associated with mental illness.

A serious condition in which the nerves at the end of the spinal cord are compressed.

A deformity of the outer ear that may occur after injury to the ear.

An immune reaction to eating gluten, a protein found in wheat, barley, and rye.

Lumpy, dimpled flesh on thighs, hips, buttocks, and belly.

A common and sometimes serious bacterial skin infection.

Swelling of the brain.

A disorder of movement, muscle tone, or posture.

Cancer of the cervix, the lower part of the uterus connected to the vagina.

The growth of cells in the cervix that look different from typical cells.

Swelling of the cervix, the lower end of the womb that opens into the vagina.

An illness caused by infection with a parasite spread by the triatomine bug.

A slow-growing, inflammatory lump in the tear gland of the eyelid.

A group of hereditary disorders that damage the nerves in the arms and legs.

A sudden, unexpected tightening of one or more muscles, often in the legs. A charley horse is another name for a muscle cramp.

Dry, cracked lips.

Damage to the skin and deeper tissues caused by chemical contact.

A common, noncancerous skin growth.

An infection of the lungs or the airways that connect the windpipe to the lungs.

Discomfort in the chest including a dull ache, a crushing or burning feeling, a sharp stabbing pain, and pain that radiates to the neck or shoulder.

A childhood infection causing an itchy, blister-like rash that can be prevented by a vaccine.

A viral infection from a mosquito bite.

Skin sores or bumps that happen after exposure to very cold temperatures.

A condition in which a child weighs well above the typical weight for age and height.

The feeling of being cold, though not necessarily in a cold environment, often accompanied by shivering.

An illness caused by infection with bacteria and spread mainly by contact with genitals or body fluids.

When a person can't breathe due to a blocked airway.

A cancer in the slender tubes that carry the digestive fluid bile through the liver.

A disease of the common bile duct.

Inflammation of the gallbladder — a small, digestive organ beneath the liver.

An illness caused by infection with bacteria and often spread through contaminated water.

Any condition in which the flow of bile from the liver stops or slows.

A cyst in the middle ear.

Damage to the cartilage under the kneecap.

A type of cancer of the uterus that spreads rapidly.

A condition that causes increasing weakness in the legs and arms.

A type of cancer of the blood and bone marrow.

A slow-growing, rare type of blood cell cancer that begins in bone marrow.

A group of lung diseases that block airflow and make it difficult to breathe.

Persistent pain that lasts weeks to years.

Long-term inflammation of the pancreas.

The gradual loss of the kidneys' ability to work.

A long-term condition in which leg veins don't properly return blood to the heart.

Scarring of the liver caused by a liver disease or condition.

Leg or arm pain from a lack of blood flow to the muscles. Usually starts during exercise and ends with rest. Often due to peripheral artery disease.

Openings or splits in the roof of the mouth.

Inflammation of the colon caused by the bacteria Clostridium difficile.

A common birth defect in which the foot is twisted out of shape or position.

A rare condition in which headaches occur in patterns or clusters.

A condition in which the blood doesn't clot as it should.

A narrowing of the body's main artery that's often present at birth.

An infection, also called valley fever, caused by coccidioides fungi.

Pain in or around the bony structure at the bottom of the spine, called the tailbone or coccyx.

Inflammation of the large intestine.

A common break of the wrist.

A reduced ability to distinguish between certain colors.

A cancer of the colon or rectum, which may begin as noncancerous polyps.

A period of prolonged unconsciousness brought on by illness or injury.

A skin pore clogged with oil, dead skin cells and bacteria, usually on the face, neck, chest, back or shoulders.

An infection of the nose and throat caused by a virus.

A common type of pneumonia that occurs outside of health care facilities.

A condition caused by too much pressure in the tissue compartments that separate muscle groups.

Chronic arm or leg pain developing after injury, surgery, stroke, or heart attack.

Thoughts, urges, or behaviors that persist despite negatively affecting health, job, or relationships.

A persistent difficulty discarding or parting with possessions because of a perceived need to save them.

Brain injury caused by a blow to the head or a violent shaking of the head and body.

A group of emotional and behavioral conditions in children and teens.

Trouble hearing that happens when sound can't fully reach the inner ear.

A group of conditions passed from parent to child that limits the making of hormones in the adrenal glands.

One or more problems with the structure of the heart that a child is born with.

A condition that occurs in a baby whose mother is infected with the rubella virus.

Two babies born physically connected to each other.

Inflammation or infection of the outer membrane of the eyeball and the inner eyelid.

A group of disorders involving the connective tissue.

Infrequent bowel movements, and small, hard-to-pass, stool.

A skin rash caused by contact with a substance.

Tightening of uterine muscles during pregnancy, often referring to contractions during childbirth.

A condition in which emotional stress is converted to physical symptoms.

A loss of consciousness accompanied by violent muscle contractions.

Thick, hardened layers of skin caused by friction and pressure.

A scratch or cut on the cornea.

A type of heart disease that affects the main heart arteries. It causes reduced blood flow to the heart muscle.

A coronavirus that spreads from person to person and causes illness.

A rare disease in which areas of the brain shrink and nerve cells die, affecting movement and thinking.

An inflammation of the cartilage that connects a rib to the breastbone.

A sudden, forceful hacking sound to release air and clear an irritation in the throat or airway.

Crusting and white or yellow scales on a baby's scalp.

A painful, involuntary contraction of a muscle.

A birth condition in which 1 or more joints in a baby's skull close too soon.

Crackling or grating sound caused by joint surfaces rubbing against each other.

A degenerative brain disorder that leads to dementia and death.

A type of inflammatory bowel disease that affects the lining of the digestive tract.

An upper airway infection that blocks breathing and has a distinctive barking cough.

Shedding tears in response to certain emotions or pain.

A testicle that hasn't moved into the bag of skin below the penis before birth.

Cushing syndrome happens when, over time, the body has too much of the hormone cortisol.

A skin disease caused by infection with a parasite that is spread through the bite of infected sand flies.

Blue or gray color of the skin, nails, lips, tongue or gums

A mood disorder that causes emotional highs and lows.

An abnormal, usually noncancerous growth filled with liquid or a semisolid substance, sometimes causing pain.

An inherited life-threatening disorder that damages the lungs and digestive system.

A tapeworm infection that forms cysts in the brain, muscle and other tissues.

A condition in which the bladder drops from its usual position in the pelvis and pushes on the wall of the vagina.

An irregular immune system response to milk and milk products.

A congenital brain condition affecting the part of the brain controlling movement.

A painful condition affecting the tendons on the thumb side of the wrist.

Complete or almost-complete loss of hearing.

A blood clot in a deep vein, usually in the legs.

Distortion or disfigurement of any part of the body.

Osteoarthritis of the spine, usually in the neck or lower back.

A significant loss of body fluid that impairs normal body functions.

Serious disturbance in mental abilities that results in confused thinking and reduced awareness of surroundings.

Severe alcohol withdrawal symptoms such as shaking, confusion, and hallucinations.

A belief or altered reality that is persistently held despite evidence or agreement to the contrary, generally in reference to a mental disorder.

An unexplained skin disorder that produces crawling sensations and skin sores.

A group of thinking and social symptoms that interferes with daily functioning.

Any condition that damages the sheath that protects the brain and spinal nerves.

A disease spread by mosquitoes that occurs in tropical and subtropical areas of the world.

A pocket of pus in a tooth caused by an infection.

Permanently damaged areas in teeth that develop into tiny holes (cavities).

A sticky film that coats teeth and contains bacteria.

The persistent feeling of observing oneself from outside one’s body or having a sense that one’s surroundings aren't real.

A persistent feeling of sadness and loss of interest.

Inflammation of the skin with many causes and forms, often causing itching and a rash.

A chronic, very itchy skin rash made up of bumps and blisters.

A condition in which scratching the skin causes raised, hive-like lines.

An inflammatory disease marked by muscle weakness and skin rash.

A small, noncancerous lump in the skin, often near the eye, present at birth. This type of lump is also called a cyst.

An unintended damage to and loss of the upper layer of skin.

A childhood developmental disorder marked by clumsiness in otherwise healthy kids.

A disease that causes the body to make large amounts of urine and can lead to extreme thirst.

A group of diseases that can cause high blood sugar.

A diabetic foot ulcer is an open sore or wound on the foot in people who have diabetes.

A serious diabetes complication in which the body makes too much of the blood acids called ketones.

A type of nerve damage that can happen with diabetes.

A complication of diabetes that affects the eyes.

Loose, watery stools that occur more frequently than usual.

Loose, watery bowel movements that may occur frequently and with a sense of urgency.

A condition in which the two large muscles in the abdomen pull apart, often during pregnancy.

Choosing types and amounts of food and drink to lose or gain weight or to keep weight steady.

A fast-growing, common cancer of the body's germ- and disease-fighting system, called the lymphatic system.

A disorder caused by a defect in chromosome 22.

A type of heart muscle disease that causes the heart chambers to thin and stretch, growing larger.

An illness caused by bacteria infecting the nose and throat or the skin that can most often be prevented with a vaccine.

Seeing two images of an object, also known as double vision.

An injury in which the upper arm bone comes out of the shoulder blade socket.

An injury in which the hip joint is moved out of place.

Condition that causes blood to clot throughout the body's blood vessels.

Disconnection and lack of continuity between thoughts, memories, surroundings, actions, and identity.

A disorder characterized by the presence of 2 or more distinct personality states.

A common condition in which one of the long bones near the wrist breaks.

A painful swelling or infection in one or more small pouches in the digestive tract.

A condition in which small, bulging pouches develop in the digestive tract.

A sac that develops in the lining of the bowel or bladder.

A range of sensations that can include feeling faint, woozy, weak, unsteady or a sense of spinning.

Bites from a pet or wild dog.

A genetic chromosome 21 disorder causing developmental and intellectual delays.

An infection from a parasite that happens in parts of Africa that don't have safe water.

The flow of saliva outside the mouth.

Death caused by suffocation when water or other liquid fills the lungs.

Physical and mental symptoms that occur after stopping or reducing intake of a drug.

Decreased moisture in the body.

The most common type of muscular dystrophy, which is a genetic condition that becomes worse over time.

A type of breast cancer that starts in a milk duct of the breast.

A gradual thickening and tightening of tissue under the skin in the hand.

Short height that results from a genetic or medical condition.

Weakness in the muscles used for speech, which often causes slowed or slurred speech.

A dysfunction of the nerves that regulate nonvoluntary body functions, such as heart rate, blood pressure, and sweating.

An infection of the intestines that causes bloody diarrhea.

An altered or impaired sense of taste.

A condition in which tiny, fluid-filled blisters appear on the palms and fingers.

A condition in which tiny, fluid-filled blisters appear on the palms and fingers.

Uncontrolled, involuntary muscle movement.

A learning disorder characterized by difficulty reading.

An imbalance of lipids and lipoproteins in the blood.

The medical name for menstrual cramps, which are throbbing or cramping pains in the lower stomach area.

Genital pain that happens just before, during or after sex.

Difficulty swallowing foods or liquids, arising from the throat or esophagus, ranging from mild difficulty to complete and painful blockage.

Difficulty speaking or using words properly.

A change in how the voice sounds. Dysphonia affects the ability to talk or sing.

A state of feeling uneasy, unhappy, or unwell.

Shortness of breath.

A mild but long-term form of depression.

Involuntary muscle contractions that cause repetitive or twisting movements.

The medical term for pain while passing urine, which can have many treatable causes.

Pain in the inner or outer ear that might decrease hearing, often caused by fluid buildup and infection.

An infection caused by Ebola virus strains.

A large, blue or purple bruise under the skin that changes color over time before fading.

Seizures and coma that happen during pregnancy or soon after childbirth.

A pregnancy in which the fertilized egg implants outside the uterus.

Extra fluid trapped in soft tissue, often in the legs and feet.

A condition that causes severe developmental delays due to an extra chromosome 18.

A common allergy in which the body reacts to the eating of eggs.

A group of illnesses passed from parent to child that mostly affect the skin, joints and blood vessels.

Physical discomfort in the elbow joint, or in the muscles, tendons and ligaments supporting it.

Injury to the body from direct contact with a high-voltage source.

Hardening and thickening of the skin caused by a disease that is spread through the bites of infected mosquitoes.

The state of being excessively thin and wasting of the body.

A blockage of blood supply to part of the brain caused by a clot or debris (embolus).

A sudden blockage of an artery by a blood clot or other mass.

Inflammation of the brain, often due to infection.

A broad term for any brain disease that alters brain function or structure.

A condition in which a child resists having bowel movements, causing impacted stool to collect in the colon and rectum and lead to leakage.

Irritation and swelling of the inner lining of the heart's chambers and valves. Usually caused by infection.

A type of cancer that begins in the lining of the womb. The womb also is called the uterus.

A growth on the inner wall of the uterus that's most often not cancer.

A disorder in which tissue similar to the tissue that lines the uterus grows outside the uterus in places where it doesn't belong.

Loss of bladder control.

A higher than usual level of disease-fighting white blood cells called eosinophils.

Inflammation of or injury to the tube connecting the mouth to the stomach, called the esophagus.

Clusters of pigment cells in the skin, also known as freckles.

A small, noncancerous small lump in the skin. This type of lump is also called a cyst.

A group of conditions in which injury, heat, or friction makes the skin blister.

Swelling of the tube at the back of a testicle that stores and carries sperm.

An accumulation of blood between the skull and brain.

A dangerous condition that happens when the small flap that covers the windpipe swells and blocks airflow into the lungs.

A disorder in which nerve cell activity in the brain is disturbed, causing seizures.

Not being able get or keep an erection firm enough for sexual intercourse.

Excess gas in the stomach or upper intestine released from the mouth, also known as burping or belching.

A skin infection that occurs mainly on the face and legs.

Inflamed skin, either in a small spot or all over.

A skin condition mostly due to an infection.

A painful disorder with lumps under the skin.

Fear of the color red, often accompanied by fear of blood or blushing.

Dead tissue that over time sloughs off healthy skin after an injury.

Cancer of the tube that runs from the throat to the stomach, called the esophagus.

Irregular veins in the lower part of the tube running from the throat to the stomach, called the esophagus.

Inflammation that damages the tube running from the throat to the stomach, called the esophagus.

A nervous system disorder that causes rhythmic shaking.

An extreme, unrealistic feeling of physical and emotional well-being, feeling "high."

A cancer that most often occurs in and around the bones.

A widely spread out rash.

Bulging of the eyes, which causes the eyes to move out of the sockets in one or both eyes.

Fluid that leaks from wounds as part of the healing process.

Physical discomfort in the eye's surface or deep within the eye, ranging from a slight irritation to severe pain.

Involuntary spasms of the eyelid muscles.

An inherited blood-clotting disorder due to a change in of the blood's factor V protein.

A condition in which a woman who isn't pregnant believes that she is.

A vision condition in which objects far away are seen more clearly than objects close up.

Involuntary twitching of voluntary muscles.

A feeling of extreme tiredness that involves a lack of energy and little ability to do everyday things.

An increased buildup of fat in the liver.

An unpleasant feeling triggered by the perception of danger, real or imagined.

Convulsion in a child that may be caused by a spike in body temperature (fever).

Hardened stool that's stuck in the rectum or lower colon due to chronic constipation.

Physical and mental damage in a child due to alcohol exposure while in the womb.

A short-term rise in body temperature that's often caused by an infection.

A prolonged fever without an established cause despite testing.

A solid breast lump that isn't cancer that can be found in anyone who has periods.

An older term for fibrocystic breasts, which are composed of tissue that feels lumpy or ropelike.

A noncancerous tumor made up of fibrous or connective tissue.

Widespread pain along with symptoms such as fatigue.

A formation of fibrous tissues.

The formation of fibrous tissue.

A rash illness that is caused by a virus.

Illness caused by infection with a parasite called a filarial worm.

The first three months of pregnancy.

A dry, sore, irritated, or cracked nipple.

When a connection forms between organs.

Loose and floppy limbs.

A condition in which the entire sole of the foot touches the floor when standing.

Intestinal gas that's passed from the anus.

Spots in vision that look like black or gray specks or strings that drift across the eyes.

Reddening of the skin.

A slow-growing type of non-Hodgkin lymphoma.

Infection of 1 or more of the pockets from which hair grows. These pockets are called follicles.

An unpleasant or dangerous immune system reaction after a certain food is eaten.

An intense desire for certain foods or flavors.

Digestive problems that happen after a certain food is eaten.

A sickness that people get from something they ate or drank.

Parasitic worm infections that cause serious liver and lung disease.

A general term for difficulty lifting the front part of the foot, sometimes called drop foot.

Physical discomfort in the foot.

A genetic condition causing intellectual disability.

The need to pass urine many times during the day, the night or both.

Sweating and flushing of a patch of skin near one ear caused by eating.

Frostbite definition

A painful, pus-filled bump under the skin caused by infected, inflamed hair follicles.

A condition causing red blood cells to break down during stress or infection.

A condition in which the body can't use a simple sugar to produce energy.

Conditions affecting the gallbladder, a small organ that helps digestion.

A hardened deposit of fluid in the gallbladder, a small organ under the liver.

A noncancerous lump, often on the tendons or joints of the wrists and hands.

Death of body tissue caused by an infection or lack of blood flow.

Symptoms that happen when stomach contents move into the small bowel before being digested.

Any of a group of conditions in which the stomach lining is inflamed.

An illness of the stomach and the intestines.

Digestive condition in which stomach acid or bile irritates the lining of the food pipe, called the esophagus.

A condition in which a hole develops in a digestive organ or tract.

A digestive tract cancer that most often occurs in the stomach or small intestine.

A condition that affects the stomach muscles and prevents proper stomach emptying.

A condition in which part of a newborn's intestines sticks out of the belly at birth.

An inherited condition in which an enzyme that breaks down fat doesn't work properly.

Severe, ongoing anxiety that interferes with daily activities.

A common sexually transmitted infection that often spreads by skin-to-skin contact during sexual activity.

A small bump caused by a virus and spread through contact with genitals or body fluids.

A condition in which the knees bow apart even when standing with feet and ankles together, also known as bowlegs.

A condition that causes harmless tongue patches resembling smooth, red islands.

A condition that causes high blood sugar during pregnancy.

An infection of the intestines that is caused by a parasite.

A rare condition that causes irregular growth and other symptoms in children.

A mild condition in which the liver doesn't properly process bilirubin.

A form of gum disease that causes inflamed gums.

A group of eye conditions that can cause blindness.

A type of cancer that starts in the brain or spine.

A growth of cells that starts in the brain or spinal cord.

The feeling of having a lump or ball in the throat.

Inflammation of the tiny filters in the kidneys that remove waste from blood.

A condition in which the tongue swells, changes color, and looks smooth.

Ongoing or recurrent burning in the mouth with no obvious cause.

Sensitivity to gluten, a protein found in wheat, barley, and rye.

A goiter is the irregular growth of the thyroid gland.

A condition that causes pain on the inner side of the elbow.

An illness caused by infection with bacteria and spread mainly by contact with genitals or body fluids.

A form of arthritis that causes severe pain, swelling, redness and tenderness in joints.

A condition that happens when donor immune cells attack the new host.

A seizure that involves a loss of consciousness and violent muscle contractions.

A small area of inflammation in tissue.

Inflamed or skin-colored bumps in a ring pattern. They often arise on the hands and feet.

A condition that causes inflammation of the blood vessels.

A disorder of the immune system that causes the thyroid gland to make too much thyroid hormone.

Sickness caused by certain species of streptococci bacteria, also called group A strep.

A term used for sickness caused by certain species of streptococci bacteria, also called group B strep.

Soreness in a child's legs that often occurs at night.

A condition in which the immune system attacks the nerves.

Feeling responsible or regretful for a perceived offense, real or imaginary.

A skin condition of tiny, drop-shaped sores on trunk, arms, or legs.

A larger amount of breast gland tissue than usual in men.

Progressive loss of hair from the scalp beyond usual hair loss of less than 100 hair strands a day.

A persistent, unpleasant odor in exhaled breath, usually not serious, commonly called bad breath.

A perception of having seen, heard, touched, tasted, or smelled something that wasn't actually there.

A noncancerous tumorlike growth.

A foot condition in which the toe has an abnormal bend in the middle joint.

A common children's virus that causes sores in the mouth and a rash on the hands and feet.

Unpleasant symptoms that occur after excessive alcohol intake.

A group of virus strains that spread through contact with rodents that cause serious bleeding or respiratory illness.

A condition in which a newborn has hard, thick skin in diamond patterns.

A disorder that happens when the immune system attacks the thyroid gland.

A group of cancers of the mouth, sinuses, nose, or throat.

The presence of lice in the hair on the head.

A painful sensation in any part of the head, ranging from sharp to dull, that may occur with other symptoms.

Trouble hearing in one or both ears that can get worse over time.

A chronic condition in which the heart doesn't pump blood as well as it should.

Sound of blood flowing through the heart, due to anything from healthy heart exertion during exercise to a diseased heart valve or other abnormality.

A condition in which one or more heart valves do not work properly.

Burning pain or discomfort in the upper chest and midchest, possibly involving the neck and throat, that may get worse when lying down.

Soreness on the back or the underside of the heel that may make walking uncomfortable or difficult.

A bony growth that forms around the heel bone, rarely causing pain.

A serious complication of high blood pressure during pregnancy.

A birthmark often appearing as a rubbery, bright red nodule of extra blood vessels.

Vomiting blood.

Bright red blood in the stool or with bowel movements.

A pool of blood outside the blood vessels.

Blood in semen.

Blood in the urine can be harmless. Or it can be a symptom of a serious illness.

Muscle weakness or partial paralysis on one side of the body that can affect the arms, legs, and facial muscles.

The breakdown of red blood cells sooner than is typical.

A condition in which red blood cells are destroyed faster than the body makes them.

A condition in which a newborn's blood is damaged by antibodies from the mother.

A condition in which a buildup of white blood cells harms the liver and spleen.

A condition in which blood doesn't clot in the typical way.

Coughing up blood, in small amounts mixed with sputum brought up by a forceful cough or large amounts of bright red blood, which is more serious.

Internal or external bleeding that may occur anywhere, and depending on the location, may range from a bruise to a life-threatening brain bleed.

Any of a group of infectious diseases that affect many of the body's organs and may lower the blood's ability to clot.

Swollen and inflamed veins in the rectum and anus that cause discomfort and bleeding.

A disorder causing inflammation and bleeding in the small blood vessels.

The loss of brain function when a damaged liver doesn't remove toxins from the blood.

An inflammation of the liver.

A highly contagious liver infection caused by the hepatitis A virus.

A serious liver infection caused by the hepatitis B virus.

An infection caused by a virus that attacks the liver and leads to inflammation.

The most common form of liver cancer.

An enlarged liver.

The bulging of an organ or tissue through an irregular opening, typically in the belly.

A common childhood illness that causes painful sores in the mouth and throat.

Infection with the herpes simplex virus around the border of the lips.

A virus that spreads from person to person, most often causing sores around the mouth or genitals.

A viral infection that causes a painful rash, also called shingles.

A condition in which the colored part of the eye (iris) is multicolored.

A condition in which part of the stomach pushes up through the diaphragm muscle.

Involuntary spasms of the diaphragm, usually short-lived and not a sign of something serious.

A chronic skin condition featuring lumps in places such as the armpits or groin.

An injury that causes the hipbone to move out of place.

A break in the upper quarter of the thighbone, near the hip joint.

Pain on the inside or outside the hip, which can be caused by arthritis, injuries or other health problems.

Swelling of the tissues, called tendons, that connect muscle to the bone in the hip joint.

A condition of the large intestine (colon) that causes difficulty passing stool.

Unwanted male-pattern hair growth on a woman's face, chest, and back.

A chronic mental condition that affects thinking, perceiving, and relating to others.

HIV infection is a long-term condition caused by a virus that also can cause a life-threatening disease called AIDS.

Welts on the skin triggered by a response to food, medicine, or other irritants.

A cancer that affects the body's germ- and disease-fighting system, also called the lymphatic system.

Symptoms of a disrupted nerve pathway from the brain to the face and eye on one side.

Feelings of opposition, unkindness, or unfriendliness toward something or someone.

Sudden feeling of heat, mostly over the face, neck and chest, as well as heavy sweating, most often due to menopause.

An infection caused by a virus that leads to the growth of warts and also may lead to cancer, depending on the strain.

A break in the upper arm bone, known as the humerus.

The sense of an empty stomach that may prompt increased appetite or craving for food.

An inherited condition in which nerve cells in the brain break down over time.

A disease, also known as cystic echinococcosis, caused by tapeworm parasites that pass from animals to people.

A fluid-filled sac around a testicle, often first noticed as swelling of the scrotum.

A buildup of fluid in the cavities deep within the brain.

Swelling in one or both kidneys due to a backup of urine.

A serious condition in which extra fluid builds up inside a fetus or newborn.

A condition in which the level of calcium in the blood becomes too high.

High amounts of the waxy substance found in fats in the blood, known as cholesterol.

Extra teeth in the mouth.

A severe type of nausea during pregnancy.

A higher-than-usual amount of blood in a body part or an organ, which can be due to an increase in blood flow into the area or a blockage out of the area.

High blood sugar levels.

Heavy sweating that's not always related to heat or exercise.

A high level of the electrolyte potassium in the blood. Potassium is a chemical that is important to the function of nerve and muscle cells, including those in the heart.

A condition in which there are high levels of fat-like substances, called lipids, in the blood.

When one or more joints can move through a wider range of motion than is usual.

A level of sodium in the blood that is higher than usual.

A condition in which one or more of the parathyroid glands in the neck make too much hormone

Patches or spots on the skin that are darker than surrounding skin.

An abnormal increase in normal cell production.

An obsession with sexual thoughts, urges, or behaviors that may cause distress or that negatively affects health, job, or relationships.

Excessive sleepiness or drowsiness.

High blood pressure; generally a blood pressure reading of 130/80 millimeters of mercury or higher.

Blood pressure of 180/120 millimeters of mercury or higher.

A dangerously overheated body, usually in response to prolonged, hot, humid weather.

A condition in which the thyroid gland makes too many hormones.

A high level of a certain type of fat, known as triglycerides, in the blood.

A disease in which the heart muscle becomes thickened, also called hypertrophied.

The enlargement of an organ.

A high level of uric acid in the blood. This can be linked to gout or kidney stones.

Rapid or deep breathing.

A condition in which too much fluid builds up in the body.

A condition in which the blood has too little calcium.

Obsession with the idea of having a serious but undiagnosed medical condition.

A decreased sense of touch or sensation, also called numbness.

A condition in which the body's blood sugar level goes below the standard range.

A condition in which the testes or ovaries don't work properly.

A low level of the electrolyte potassium in the blood. Potassium is important to the proper functioning of nerve and muscles cells, particularly heart muscle cells.

Slowed or reduced muscle movement.

A condition that occurs when the level of sodium in the blood is too low.

A rare congenital heart defect, in which the left side of the heart doesn't develop fully and is too small.

A condition in which the opening that drains urine is on the underside of the penis.

Low blood pressure.

When the body loses heat faster than it can produce heat, causing a dangerously low body temperature.

A condition in which the thyroid gland doesn't make enough thyroid hormones.

Weak muscle tone.

A condition in which the body is too low on vitamin D, a nutrient that is important for bones, nerves, muscles and the immune system.

A condition in which the liquid portion of the blood, called plasma, is too low.

A low level of oxygen in the blood.

An absence of enough oxygen in the blood to sustain bodily functions.

The creation of additional problems or complications resulting from medical treatment.

A group of skin disorders that cause dry, scaly, or thick skin.

Low levels of the blood cells that prevent bleeding, called platelets.

Inability of the intestine (bowel) to contract normally and move waste out of the body.

A painful knee condition often caused by running long distances.

A highly contagious skin infection that causes red sores on the face.

Shoulder pain caused by connective tissue rubbing on a shoulder bone.

A problem with emotional or behavioral self-control.

A group of conditions in which the body can't properly convert food into energy.

Upper abdominal discomfort, described as burning sensation, bloating or gassiness, nausea, or feeling full too quickly after starting to eat.

A yellow color to the skin in newborns caused by high bilirubin levels, a condition that must be closely watched.

Tissue death from reduced blood supply.

A disease caused by a virus that spreads through saliva.

Not getting pregnant despite having frequent unprotected sex for one year.

An immune response that causes redness and swelling on or within the body.

Ongoing inflammation of all or part of the intestines.

A form of breast cancer that develops quickly, causing breast swelling and skin changes.

A common, sometimes deadly viral infection of the nose, throat and lungs, also called flu.

A shaved or tweezed hair that grows back into the skin, causing swelling.

A condition in which soft tissue bulges through a weak point in the abdominal muscles.

The bite of an insect, such as a bee or mosquito, which usually causes mild symptoms.

Persistent problems falling or staying asleep or both.

A resistance to the hormone insulin, resulting in increasing blood sugar.

Below average intelligence and set of life skills present before age 18.

Menstrual bleeding that happens between periods and can be monthly or random.

Bleeding inside the body, particularly in the chest or belly cavities, or into muscles.

Bladder pain and having to urinate often are common with this condition.

A group of disorders that cause progressive scarring of lung tissue.

Inflamed skin, usually in warm, moist areas, such as the groin or between skin folds.

A weakness in a blood vessel in the brain that balloons and fills with blood.

A condition in which a baby does not grow as expected during pregnancy.

A condition in which part of the intestine slides into an adjacent part of the intestine.

A nipple that's turned inward.

A lack of iodine in the diet.

A condition of too little iron in the body.

Too few healthy red blood cells due to too little iron in the body.

Too much iron in the body.

Missed, delayed, or inconsistent periods or menstrual bleeding patterns that are out of the ordinary.

Feelings of frustration or anger, often over seemingly small matters.

An intestinal condition causing pain in the belly, gas, diarrhea and constipation.

A patchwork of inflamed skin on a baby's bottom that's known as diaper rash.

Reduced blood flow.

Intense itching, inflammation, burning or soreness in or around the anus.

An illness caused by a virus that is spread through the bites of infected mosquitos.

Yellow skin caused by the buildup of bilirubin in the blood.

A yellow tint to the skin or eyes caused by an excess of bilirubin, a substance created when red blood cells break down.

Physical discomfort in the jaw.

A sleep disorder that can affect those who travel quickly across multiple time zones.

An injury where bone joints are forced out of their usual position.

Physical discomfort where two or more bones meet to form a joint. Pain can range from mild to disabling.

A form of arthritis that affects children.

A cancer that causes lesions in the soft tissues.

A condition that causes swelling in the walls of some blood vessels in the body.

A raised scar after an injury has healed.

Inflammation of the clear tissue on the front of the eye (cornea).

Dry eye that occurs when tears aren't able to provide adequate moisture.

A condition in which the clear tissue on the front of the eye (cornea) bulges outward.

A condition that causes rough patches and small, tiny bumps on the skin.

Life-threatening disturbance of metabolism most often seen in uncontrolled diabetes.

Pain that starts in the pair of organs located in the back below the ribs.

A small, hard deposit that forms in the kidney and is often painful when passed.

An impulse control disorder that results in an irresistible urge to steal.

A genetic condition in which a boy is born with an extra copy of the X chromosome.

Pain in or around the knee that can be due to an injury or a medical condition.

Malnutrition caused by a serious lack of protein in the diet.

An excessive forward rounding of the upper back.

Swelling of the inner ear that can cause problems with hearing and balance.

A condition in which lactic acid builds up in the blood faster than it can be removed.

Not being able to fully digest sugar, called lactose, in dairy products.

An inflammation of the voice box, which is also known as the larynx. Overuse, irritation or infection can be the cause.

Decreased vision due to abnormal visual development.

A buildup of lead in the body, often over months or years.

A disorder that affects ability to learn and use academic skills, such as reading and math.

A delay or blockage of electrical signals to the left side of the heart.

Thickening of the walls of the lower left heart chamber, called the left ventricle.

Physical discomfort in part or all of the leg that can vary in strength.

A noncancerous soft tissue tumor that develops from smooth muscle.

A disease caused by a parasite that is spread through the bite of infected sand flies.

A chronic, curable infectious disease mainly causing skin lesions and nerve damage.

An illness caused by bacteria that spread to humans through contact with the urine of infected animals.

An irregular area of tissue inside or outside the body that may get bigger or change appearance. It may or may not be cancerous.

Ongoing tiredness that reduces energy, being able to do things and being able to focus.

A cancer of the body's blood-forming tissues. It can harm the ability to fight infection.

A high level of white blood cells in the blood. A high white blood cell count can be caused by infection, reaction to a medicine, a bone marrow disease, an immune system issue, smoking or sudden stress such as hard exercise.

A low level of white blood cells in the blood, which can interfere with the ability to fight infection.

Thickened, white patches inside the mouth.

The medical name for vaginal discharge, a mix of fluid and cells that typically helps keep the vagina healthy and clean.

A chronic condition that causes patchy, discolored, thin skin. It often affects the genital and anal areas.

Feeling dizzy or about to faint.

An unsteady walk that can be caused by pain, weakness or injury to the leg.

A fatty lump most often between the skin and muscle.

An illness caused by infection with bacteria and spread through contaminated food.

Cancer that begins in the cells of the liver.

Loss of liver function.

A noncancerous mass in the liver.

Physical discomfort in the liver, an organ located in the upper right belly.

Flat tan, brown, or black spots on the skin common with age.

Feeling sad and unhappy about being socially isolated.

A heart rhythm disorder that can cause fast, chaotic heartbeats.

Inward curving of the spine in the neck and lower back.

The inability to respond to surroundings or stimuli.

Partial or complete loss of the sense of smell.

Physical discomfort with pain affecting the lower half of the back. It can vary in intensity from a dull ache to disabling.

Bleeding from the small intestine, large intestine, rectum or anus.

Bleeding from the small intestine, large intestine, rectum, or anus.

A disease of the root of a nerve in the lower (lumbar) spine.

A narrowing of the open spaces in the lower spine, known as the lumbar spine.

A cancer that begins in the lungs and most often occurs in people who smoke.

A long-term illness that occurs when the immune system attacks its own tissues and organs.

An illness caused by borrelia bacteria that usually is spread through the bite of an infected tick.

An infection of the lymph system with a parasite called a filarial worm.

Swelling, most often in an arm or leg, caused by a lymphatic system blockage.

Cancer that affects the body's germ- and disease-fighting system, also called the lymphatic system.

An eye disease that causes vision loss.

A brain disorder in adult cattle that may be spread to humans through diseased meat.

A low level of the mineral magnesium in the body.

A mood disorder causing a persistent feeling of sadness and loss of interest.

A condition that prevents absorption of nutrients through the small intestine.

Learn more about this general sense of not feeling well.

A disease caused by a parasite, spread by the bites of infected mosquitoes.

Severe reaction to anesthesia drugs causing a high temperature and muscle break down.

To intentionally pretend to have a disease in order to achieve another goal.

Unbalanced nutrition, which can be undernutrition or overnutrition.

The abnormal alignment of the upper and lower teeth.

Breast cancer that starts in a milk duct of the breast.

Extremely elevated and excitable mood usually associated with bipolar disorder.

Condition that makes it hard to break down certain parts of protein (amino acids).

Severe malnutrition with muscle and fat wasting.

An inherited disorder that affects connective tissue.

Painful swelling and change in skin color, called inflammation, of breast tissue most often in people who are breastfeeding.

Too many of a type of disease-fighting and wound-healing cells (mast cells).

An infection caused by germs called bacteria that affect the mastoid bone behind the ear.

This once common childhood infection most often can be prevented with a vaccine.

A severe form of depression.

A noncancerous mole caused by a disorder of pigment-producing skin cells.

The most serious type of skin cancer.

A condition in which patches of skin on the face darken. It's also called the mask of pregnancy.

Dark tarry stool with or without visible blood.

An inner ear disease that can cause a spinning feeling, ringing in the ear and trouble hearing.

A tumor that arises from the membranes surrounding the brain and spinal cord.

Inflammation of brain and spinal cord membranes, typically caused by an infection.

A serious bacterial infection that affects the brain and spinal cord.

Irritation and swelling, called inflammation, of the brain and the tissues around it, most often caused by infection.

The permanent end of fertility, signaled by 12 months since last period.

Heavy or long-lasting vaginal bleeding during periods.

A type of condition that causes irregular or painful menstrual periods.

Inability to think or reason in a focused, clear manner.

A nerve condition characterized by tingling, numbness, and pain in the outer thigh.

A respiratory illness that is caused by a virus.

A cancer that starts in the thin layer of tissue covering the lungs, stomach, heart and other organs.

A condition in which too much acid builds up in the body.

Too much of a chemical called bicarbonate in the body.

A cluster of conditions that increases the risk of heart disease, stroke, and diabetes.

Pain and irritation of the ball of the foot.

A sprain of the main joint in the big toe, also called turf toe.

A penis that is much smaller than average.

Discomfort in the area of the spine between the base of the neck to the bottom of the ribcage.

An intense headache often accompanied by nausea and sensitivity to light and sound.

A tiny, white bump that commonly appears on a baby's face.

A skin condition caused by blocked sweat ducts and trapped sweat beneath the skin.

Contraction of the pupil, which can be temporary or permanent, depending on the cause.

The sudden loss of a pregnancy before the 20th week.

A strong reaction to specific sounds.

A disorder that happens when structures inside cells that make energy don't work properly.

Improper closure of the valve between the heart's upper and lower left chambers.

This type of heart valve disease causes blood to flow backward across the mitral valve.

A tumor that develops in the uterus as a result of a nonviable pregnancy.

A mole (pigmented skin lesion).

A viral skin infection that results in round, firm, painless bumps.

A large, blue-gray birthmark.

An abrupt change in mood or emotional state.

Wanting to throw up with or without throwing up during pregnancy at any time of day.

A thickening of the tissue around a nerve leading to the toes.

Illness caused by motion during travel.

One or more painful sores on inner lips, gums, tongue, roof of the mouth, or throat that may interfere with eating, such as a canker sore.

A cancer of plasma cells.

A disease in which the immune system breaks down the protective coating of nerve fibers in the brain and spinal cord, called the myelin sheath.

An illness caused by a virus that usually affects the glands on each side of the face.

A severe mental condition in which someone pretends to be sick for no obvious reason.

A severe mental condition in which someone imposes symptoms on a healthy person.

Soreness and achiness in the muscles that can range from mild to severe.

Aching, tender muscles.

Involuntary contractions of a muscle, typically harmless and temporary, but can be painful.

Decreased strength in the muscles.

A group of genetic diseases that causes muscles to become weaker and lose mass over time.

Extreme fatigue that can't be explained by an underlying medical condition.

A weakness and rapid fatigue of muscles under voluntary control.

Any disease that is caused by a fungus.

Dilated pupils, which may occur normally or in response to a trauma, illness, or drugs.

A group of disorders caused by blood cells that are poorly formed or don't work right.

A serious bone marrow condition that harms the making of blood cells.

A nervous system disorder that affects the spinal cord.

A blockage of blood flow to the heart. Also called a heart attack.

Inflammation of the heart muscle.

A sudden, involuntary muscle jerk, shake, or spasm.

A condition of ongoing muscle pain.

A disease of the muscles.

A condition in which close objects appear in focus, but far ones don't. Also called nearsightedness.

Swelling, called inflammation, in the muscles.

A muscle disease featuring an inability to relax muscles at will.

A complication of severe hypothyroidism that can lead to serious health problems.

An irregular, rounded shape of the nail bed.

Personality qualities include thinking very highly of oneself, needing admiration, believing others are inferior, and lacking empathy for others.

A disorder in which a person has an inflated sense of self-importance.

A sleep condition that causes people to feel very drowsy and to fall asleep suddenly.

The inside of the nose can swell with fluid and mucus. Infection, tobacco smoke or perfume can be the cause.

A painless growth inside the nose or the hollow areas inside the bones of the face, also known as sinuses.

Off-center position of the wall between the nostrils, making one entry into the nose, also known as the nasal passage, smaller.

A cancer that starts in the area behind the nose and above the back of the throat, called the nasopharynx.

A queasy sensation including an urge to vomit.

Pain in the neck and shoulder that varies in intensity. It may feel dull and achy or like an electric shock from the neck to the arm.

Death of cells or tissue through disease or injury.

An infection caused by bacteria that spreads quickly through the body and destroys tissue.

Getting stuck by a needle that has someone's blood or other body fluid on it.

Red bumps that appear on a baby's cheeks, nose, and forehead.

A liver condition that causes yellowing of a newborn baby's skin and eyes.

A breathing disorder in newborns caused by immature lungs.

A life-threatening illness in newborn babies caused by infection with germs called bacteria.

Swelling, also called inflammation, of the kidneys.

A disease in which the body has trouble balancing fluid levels due to a kidney problem.

A kidney condition that causes the body to pass too much protein in the urine.

A condition in which a nerve is damaged due to overuse or compression.

Damage to a nerve.

Pain caused by damaged or irritated nerves.

Pain that travels along the length of a nerve.

A cancer that grows from immature nerve cells, most often in the adrenal glands.

A deterioration of the nerves.

A cancer that starts in the neuroendocrine cells.

A condition that causes tumors to form in the brain, spinal cord, and nerves.

Condition in which the bladder doesn't function properly due to brain or nerve damage.

A life-threatening nervous system reaction to certain drugs.

A group of diseases that affect nerve and muscle function.

A disorder that causes swelling of the eye nerves and the spinal cord.

Breaking down of a joint from nerve damage caused by diabetes.

An abnormally low count of a type of white blood cell called neutrophils.

Is the term for physical and mental symptoms that happen after stopping or lessening use of tobacco products.

A lot of perspiring during sleep, usually has an underlying cause such as menopause, an illness, or medicine side effect.

Episodes of screaming, intense fear, and flailing while still asleep, often paired with sleepwalking.

Frightening dreams, usually during REM sleep, that are normal and common in children under 10 and can also affect teens and adults.

A dry, sore, irritated, or cracked nipple.

Urinating frequently at night.

Nighttime loss of bladder control, or bed-wetting, usually in children.

Fluid-filled or solid lump that often doesn't indicate anything serious is wrong.

Cancer that starts in the body's germ-fighting system, called the lymphatic system.

One of two major types of lung cancer that can affect smokers and nonsmokers.

The accumulation of liver fat in people who drink little or no alcohol.

A genetic condition preventing normal development in parts of the body.

When a person bleeds from the nose.

Coin-shaped rash or sores.

Any condition caused by poor diet or the inability of the body to use certain nutrients.

An involuntary eye movement which may cause the eye to rapidly move from side to side, up and down, or in a circle, and may slightly blur vision.

A disorder that involves having too much body fat, which increases the risk of health problems.

Excessive thoughts (obsessions) that lead to repetitive behaviors (compulsions).

A condition in which breathing stops and starts during sleep.

A severe headache that begins at the back of the neck and spreads upward.

Pain while swallowing.

Inflammation or irritation of a small sac of fluid, known as the olecranon bursa, on the tip of the elbow.

Much less urination than usual.

An infection of the skin and eyes also known as river blindness and caused by a parasite called a filarial worm.

A condition in which the corner or side of a toenail grows into the flesh.

A nail fungus causing thickened, brittle, crumbly, or ragged nails.

An infection with various causes that can be dangerous if the immune system is weakened.

A disorder in a child marked by defiant and disobedient behavior to authority figures.

Inflammation of the optic nerve.

Cancer that develops in any part of the mouth.

An infection in which the fungus Candida albicans accumulates in the mouth.

A noncancerous mucus-containing salivary gland cyst.

Swelling called inflammation that affects one or both testicles.

Discomfort when breathing while lying down flat; common in people with some types of heart or lung conditions.

A form of low blood pressure that happens when standing after sitting or lying down.

Painful swelling called inflammation that affects the area just below the knee.

The process of bone being formed, which can cause symptoms if bone grows in soft tissue where it doesn't belong.

Type of arthritis that occurs when flexible tissue at the ends of bones wears down.

A group of disorders passed through families that cause fragile bones that break easily.

An infection in a bone.

A condition in which bones become weak and brittle.

A type of bone cancer that begins in the cells that form bones.

Irritation and swelling of the ear, often from infection.

An infection of the outer ear canal, also called swimmer's ear. The outer ear canal runs from the eardrum to the outside of the head.

An infection of the air-filled space behind the eardrum, also known as the middle ear.

A cancer that begins in the organs that produce eggs, called the ovaries.

A sac, usually filled with fluid, in or on an ovary.

A condition in which the ovaries swell and get painful from excess hormone.

A condition that causes a frequent and sudden urge to urinate that may be hard to control.

Weight above what's considered healthy, often measured using body mass index (BMI).

One-sided, lower belly pain linked to ovulation.

An imbalance between levels of antioxidants and free radicals in the body.

A disease that disrupts the replacement of old bone tissue with new bone tissue.

A form of breast cancer affecting the nipple and dark circle of skin around it.

Physical discomfort ranging from mild to serious, usually caused by injury, illness or a nerve condition.

An ongoing condition that causes bladder pressure and pain.

A loss of color in the skin and mucous membranes, often related to anemia.

A feeling that the heart is racing, pounding, fluttering or skipping a beat. Can be caused by stress, exercise, medicines or a health condition.

Cancer that begins in the organ lying behind the lower part of the stomach, called the pancreas.

An inflammation of the organ lying behind the lower part of the stomach (pancreas).

Condition in which blood has fewer red cells, white cells and platelets than usual.

A sudden episode of intense fear that triggers severe physical reactions when there is no real danger or apparent cause.

Sudden episode of intense fear or anxiety and physical symptoms, based on a perceived threat rather than imminent danger.

Repeated episodes of sudden and intense fear when no real danger exists.

The most common form of cancer of the thyroid, a butterfly-shaped gland in the neck.

Small bump on the skin that sometimes hurts.

Complete or partial loss of muscle function.

A group of symptoms that develops in some people who have cancer.

An unrealistic distrust of others or a feeling of being persecuted. Extreme degrees may be a sign of mental illness.

Sexual behaviors generally considered harmful or unacceptable or that are illegal.

Paralysis that affects all or part of the trunk, legs, and pelvic organs but not the arms.

Partial loss of muscle function.

Tingling or prickling, “pins-and-needles” sensation; usually temporary, often occurs in the arms, hands, legs, or feet.

A disorder of the nervous system that affects movement, often including tremor.

An infection of the tissue folds around the nails.

Inflammation of 1 or both of the largest saliva-producing glands inside the cheeks.

A pattern of indirectly expressing negative feelings instead of openly addressing them.

A condition in which a person has an extra chromosome 13.

An injury to the tissue that joins the kneecap to the shinbone, called the patellar tendon.

A condition in which the cartilage under the kneecap is damaged due to injury or overuse. The kneecap also is known as the patella.

A heart defect caused by problems in the heart's development.

Inappropriate involuntary laughing and crying due to a nervous system disorder.

The compulsive urge to lie about matters big and small, regardless of the situation.

A condition in which the breastbone juts out more than usual.