Health Terms Glossary
Medical terms explained in simple, easy-to-understand language (88 terms)
A (7 terms)
Sudden onset or short-term condition.
In simple words:
Something that happens quickly or doesn't last long.
An immune system reaction to a substance that is usually harmless.
In simple words:
When your body reacts badly to something like food, pollen, or medicine.
When you don't have enough healthy red blood cells to carry oxygen to your body's tissues.
In simple words:
Having too few healthy red blood cells, which makes you feel tired and weak.
A medicine that kills bacteria or stops them from growing.
In simple words:
Medicine that fights infections caused by bacteria.
A blood vessel that carries blood away from the heart to the rest of the body.
In simple words:
A tube that carries blood from your heart to other parts of your body.
A condition where airways narrow and swell, making breathing difficult.
In simple words:
A breathing problem that makes it hard to get air in and out of your lungs.
When the body's immune system attacks its own healthy cells.
In simple words:
When your body's defense system attacks your own healthy parts by mistake.
B (5 terms)
Not cancerous; not harmful.
In simple words:
Not dangerous to your health; not cancer.
Removal of a small piece of tissue for examination under a microscope.
In simple words:
Taking a tiny sample of body tissue to test for disease.
The force of blood pushing against the walls of your arteries as your heart pumps.
In simple words:
How hard your blood pushes against your blood vessel walls.
A measure of body fat based on height and weight.
In simple words:
A number that shows if your weight is healthy for your height.
Inflammation of the lining of your bronchial tubes, which carry air to your lungs.
In simple words:
When the tubes that carry air to your lungs get swollen and irritated.
C (5 terms)
A disease where abnormal cells divide without control and can invade other tissues.
In simple words:
A disease where bad cells grow too fast and can spread to other parts of the body.
A waxy substance found in your blood. Your body needs some cholesterol, but too much can build up in your arteries.
In simple words:
A fatty substance in your blood that can build up and cause heart problems if there's too much.
Lasting for a long time or constantly recurring.
In simple words:
Long-lasting or keeps coming back over time.
Computerized tomography scan; uses X-rays to make detailed pictures of your body.
In simple words:
A special X-ray test that takes detailed pictures of inside your body.
A closed sac filled with fluid, air, or other material.
In simple words:
A small sac or bump filled with fluid that can form anywhere in your body.
D (6 terms)
When your body loses more fluids than it takes in.
In simple words:
Not having enough water in your body.
A mental health condition causing persistent feelings of sadness and loss of interest.
In simple words:
Feeling very sad, hopeless, or empty for a long time.
A disease that affects how your body uses blood sugar (glucose).
In simple words:
A condition where there's too much sugar in your blood because your body can't use it properly.
The identification of an illness or problem by examining symptoms.
In simple words:
Finding out what health problem someone has.
The bottom number in a blood pressure reading that measures the pressure in your arteries when your heart rests between beats.
In simple words:
The lower number in blood pressure that shows pressure when your heart is resting.
A medicine that helps your body get rid of extra water and salt through urination.
In simple words:
Medicine that makes you urinate more to remove extra water from your body.
E (5 terms)
Electrocardiogram; a test that measures the electrical activity of your heart.
In simple words:
A test that checks how your heart is working by measuring its electrical signals.
A blockage in a blood vessel caused by a blood clot or other material.
In simple words:
When something blocks a blood vessel, stopping blood flow.
A procedure using a flexible tube with a camera to look inside your body.
In simple words:
Using a thin tube with a tiny camera to look inside your body.
A protein that helps speed up chemical reactions in your body.
In simple words:
A special protein that helps your body do important chemical work.
A disease that spreads rapidly among many people in a community.
In simple words:
When a disease spreads quickly to many people in an area.
F (4 terms)
A break in a bone.
In simple words:
A broken bone.
A condition causing widespread muscle pain and tenderness.
In simple words:
A condition that causes pain and tenderness all over your body.
A viral infection that attacks your respiratory system.
In simple words:
A virus that makes you feel very sick with fever, body aches, and breathing problems.
A B vitamin that helps make healthy red blood cells.
In simple words:
A vitamin that helps your body make healthy blood cells.
G (4 terms)
Inflammation of the stomach lining.
In simple words:
When the inside of your stomach gets irritated and swollen.
The study of genes and how traits are passed from parents to children.
In simple words:
How characteristics like eye color and health conditions are passed from parents to children.
A simple sugar that is an important energy source for your body.
In simple words:
A type of sugar that gives your body energy.
A type of arthritis caused by too much uric acid in the blood.
In simple words:
A painful joint condition caused by too much of a certain acid in your blood.
H (5 terms)
Heavy bleeding, either inside or outside the body.
In simple words:
Heavy bleeding that doesn't stop easily.
Inflammation of the liver, often caused by a virus.
In simple words:
When your liver gets swollen and irritated, usually from a virus.
When an organ pushes through a weak spot in the muscle or tissue that holds it in place.
In simple words:
When a body part pushes through a weak spot in the muscle wall.
High blood pressure.
In simple words:
When your blood pushes too hard against your blood vessel walls.
Low blood sugar.
In simple words:
When there's not enough sugar in your blood, making you feel weak or shaky.
I (4 terms)
Your body's defense system against infections and diseases.
In simple words:
Your body's natural protection against germs and sickness.
Your body's response to injury or infection, causing redness, swelling, and pain.
In simple words:
When a part of your body gets red, swollen, and sore as it tries to heal.
A hormone that helps your body use sugar for energy.
In simple words:
A hormone that helps your body use sugar from food for energy.
Given directly into a vein through a needle or tube.
In simple words:
Medicine or fluids given through a needle directly into your blood vessel.
J (2 terms)
Yellowing of the skin and eyes, often due to liver problems.
In simple words:
When your skin and the whites of your eyes turn yellow, usually from liver problems.
Where two bones meet and connect.
In simple words:
The place where two bones come together, like your knee or elbow.
K (2 terms)
Hard deposits made of minerals and salts that form inside your kidneys.
In simple words:
Small, hard pieces that form in your kidneys and can cause severe pain.
Chemicals your body makes when it breaks down fat for energy.
In simple words:
Chemicals your body makes when it burns fat instead of sugar for energy.
L (3 terms)
An area of tissue that has been damaged by disease or injury.
In simple words:
A damaged or abnormal area on your body.
Cancer of the blood-forming tissues.
In simple words:
A type of cancer that affects your blood and bone marrow.
Small, bean-shaped structures that filter harmful substances from your body.
In simple words:
Small glands that help fight infection by filtering out germs.
M (5 terms)
Cancerous; able to spread to other parts of the body.
In simple words:
Cancerous; dangerous because it can spread.
The chemical processes in your body that convert food into energy.
In simple words:
How your body turns food into energy.
A severe headache often accompanied by nausea and sensitivity to light.
In simple words:
A very bad headache that can make you sick to your stomach and sensitive to light.
Magnetic Resonance Imaging; uses magnets to create detailed pictures of your body.
In simple words:
A test that uses magnets to take detailed pictures of inside your body.
A slippery substance produced by your body to protect and lubricate tissues.
In simple words:
A slimy substance your body makes to protect and keep tissues moist.
N (3 terms)
The feeling that you might vomit.
In simple words:
Feeling sick to your stomach like you might throw up.
The study of the nervous system and brain.
In simple words:
The medical field that deals with the brain and nerves.
A small, round growth or lump.
In simple words:
A small bump or growth on your body.
O (3 terms)
Having too much body fat, which can harm your health.
In simple words:
Being very overweight in a way that can hurt your health.
The study and treatment of cancer.
In simple words:
The medical field that deals with cancer.
A condition where bones become weak and brittle.
In simple words:
When your bones become weak and break easily.
P (4 terms)
When you can feel your heart beating fast, hard, or irregularly.
In simple words:
When you can feel your heart beating in an unusual way.
An infection that inflames air sacs in one or both lungs.
In simple words:
A lung infection that makes it hard to breathe.
The likely course and outcome of a disease.
In simple words:
What doctors think will happen with your illness.
The rhythmic beating of your heart that you can feel in your wrist or neck.
In simple words:
The beating of your heart that you can feel by touching your wrist or neck.
Q (1 terms)
Keeping someone away from others to prevent the spread of disease.
In simple words:
Staying away from other people to stop a disease from spreading.
R (3 terms)
High-energy rays used to treat cancer or take medical images.
In simple words:
Special rays used to treat cancer or take pictures inside your body.
When signs and symptoms of cancer are reduced or disappear.
In simple words:
When cancer gets better or goes away, at least for a while.
Related to breathing and the lungs.
In simple words:
Having to do with breathing and your lungs.
S (5 terms)
Sudden, uncontrolled electrical activity in the brain.
In simple words:
When the brain has sudden electrical activity that can cause shaking or loss of consciousness.
A life-threatening response to infection.
In simple words:
When your body's response to infection becomes dangerous.
When blood flow to part of the brain is blocked or reduced.
In simple words:
When part of the brain doesn't get enough blood, causing brain damage.
A sign of disease or illness that you can feel or notice.
In simple words:
Something you feel or notice that might mean you're sick.
The top number in blood pressure that measures pressure when your heart beats.
In simple words:
The higher number in blood pressure that shows pressure when your heart pumps.
T (3 terms)
Formation of a blood clot inside a blood vessel.
In simple words:
When blood forms a clot inside a blood vessel.
An abnormal growth of tissue that can be benign or malignant.
In simple words:
An abnormal growth in your body that can be harmless or cancerous.
A gland in your neck that controls how your body uses energy.
In simple words:
A gland in your neck that controls how fast your body works.
U (2 terms)
A test that uses sound waves to create pictures of inside your body.
In simple words:
A test that uses sound waves to take pictures of your baby or organs.
A test that examines your urine for signs of disease.
In simple words:
A test that checks your urine for health problems.
V (3 terms)
A substance that helps your body build immunity to a disease.
In simple words:
A shot that helps protect you from getting certain diseases.
A tiny germ that can cause infections and diseases.
In simple words:
A very small germ that can make you sick.
Basic measurements of your body's functions like temperature, pulse, and blood pressure.
In simple words:
Basic measurements that show how your body is working.
W (1 terms)
Cells that help your body fight infections.
In simple words:
Special blood cells that help fight germs and keep you healthy.
X (1 terms)
A test that uses radiation to take pictures of bones and organs inside your body.
In simple words:
A test that takes pictures of your bones and organs using special rays.
Y (1 terms)
An infection caused by too much yeast growing in your body.
In simple words:
An infection that happens when too much yeast grows in your body.
Z (1 terms)
A disease that can spread from animals to humans.
In simple words:
A disease that people can catch from animals.
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