Glossary of Terms

This glossary of terms is meant to help everyone understand medical words. It is a place to quickly find information on medical words.

To find a word or term begin by clicking on a letter in the A-Z list. Then you can browse down the list to find the word you want. You can also type your medical word in the search box in the upper right corner and then click on the little magnifying glass.

This glossary is for information only. It should never be used instead of advice from a healthcare provider.

If you have questions or comments about the Glossary of Terms please let us know.

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when your heart beats faster than normal

faster than normal heart rate


when your breathing is faster than normal

faster than normal breathing

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a way that your doctor and nurse can keep track of how your heart is beating.

used for patients who are at risk of abnormal heart activity. Sticky pads are attached to a person's chest to measure, record and transmit data to a portable ECG machine which monitors your condition. This data can be useful in diagnosis of the your condition by your doctor. An alarm can also alert your health care team if you are suffering from an acute condition or your condition worsens. 

teratogen (teratogenic)

something that can hurt your baby before he or she is born

drug or other substance that can interfere with the development of a fetus, causing birth defects


 not curable, deadly, fatal


stop, end


male hormone

tetanus (lockjaw)

a disease that affects your muscles

Tetanus (also known as lockjaw) is an infection spread by bacteria. The bacteria lives in dirt, soil and dust, but can also be found in human and animal feces (poop). If you have even a tiny cut in your skin, tetanus bacteria can get in. The infection affects the nerves that control your muscles


healing, improving, getting better

thoracentesis (pleural tap)

procedure to remove fluid from the space between your lungs and your chest wall. This space is called the pleural space

procedure to remove fluid or air from the pleural space in your chest. A  hollow needle, is carefully inserted into the thorax, generally after administration of local anesthesia. 


the chest and back area from your neck down to your lowest rib


the part of your body between your neck and your abdomen


low platelet count


a butterfly shaped gland in your neck

one of your endocrine glands, which make hormones. Thyroid hormones help control the  many activities in your body. These include how fast you burn calories and how fast your heart beats.


to change the dose of a medication


blood test

a test that measures the concentration of a solution. For example-the antibody titre detects the presence and measures the amount of antibodies within the blood

TMJ (temporomandibular joint)

the joint between your lower jaw and the bottom of your skull


an operation to remove your tonsils


an infection that causes your tonsils to be swollen and red



two lumps of tissue at the back of your throat that help fight infections

total parenteral nutrition (TPN)

is a way of getting nutrition into your body through your veins

nutrition that is provided via intravenous. Consists of electrolytes, glucose, vitamins and minerals as well as fats. Used if someone is unable to be fed orally or via nasogastric (NG) tube.


study of harmful things

the branch of science concerned with the nature, effects, and detection of poisons




windpipe, breathing tube, air tube

tube that takes air into your lungs


an operation to make an opening through your neck into your trachea to help you breathe better


pulling on part of your body to stretch muscles or to put bones or joints back in place

transbronchial cryobiopsy (cryobiopsy)

a procedure to find and diagnose interstitial lung disease

Transbronchial cryobiopsy is done under general anesthesia. This means that you won’t be awake during the procedure. The cryobiopsy is done at the same time as a bronchoscopy.

During a bronchoscopy the doctor uses a flexible, hollow tube to see the inside of your lungs and airways. This tube is called a bronchoscope. The bronchoscope is placed through your nose or mouth and is fed down towards the airways of your lungs.

In a cryobiopsy, a thin, flexible tube with a blunt metal tip (called a cryoprobe) is placed through the bronchoscope. It is moved towards the tissue  in your lung. When the metal tip reaches the best location in your lung tissue, it is cooled quickly to a very cold temperature. The cold metal tip of the cryoprobe sticks to the lung tissue around it. Then the cryoprobe and a piece of tissue are carefully pulled out of your lungs with the bronchoscope.


transesophageal echocardiogram (TEE)

a test that makes pictures of your heart

TEE uses high-frequency sound waves (ultrasound) to make detailed pictures of your heart and the arteries that lead to and from it

a special echocardiogram where a probe is inserted into the mouth and throat. It is done when your doctor want a closer look at your heart and valves (see heart tests)

transfemoral aortic valve intervention (TAVI)

procedure that allows your aortic valve to be replaced using a long narrow tube called a catheter. Usually, the catheter is inserted into a large blood vessel in your groin or through a small incision in your chest

a surgical procedure for aortic valve replacement (see conditions and treatments/TAVI)


when someone sees themselves as being a different sex than their birth sex

transgender surgery

sex change operation

transient ischemic attack (TIA)

stroke symptoms that come and go quickly

a TIA is sometimes called a “mini-stroke” is a serious warning sign of stroke risk. It is a temporary loss of blood supply to part of your brain. Even though your symptoms may last a short time, from a few seconds to several minutes, you should never ignore a TIA ! Your chance of stroke following a TIA is high.


see-through, clear

transverse myelitis

back disease, inflammation of your spinal cord


injury, damage, wound; cut, lesion, abrasion, contusion

upset, shock, distress, stress, strain, pain, anguish, suffering


to sort

when you get to the emergency department (ED) you will meet the hospital triage nurse. The triage nurse will check your condition, as well as any changes, and will decide on your priority for the ED and also for treatment

tricuspid regurgitation

when your heart valve does not close tight enough and is floppy

trigeminal neuralgia

face pain caused by pressure on a nerve


three months, time span of three months

pregnancy is divided into three trimesters, each approximately 13 to 14 weeks long. Generally speaking, each trimester is marked by different phases of fetal development.

tuberculosis (TB)

a disease of your lungs

a potentially serious infectious disease that mainly affects your lungs. The bacteria that cause tuberculosis are spread from one person to another through tiny droplets released into the air when you cough and sneeze


a small tube

a tube in the nephron which collects and processes urine from the glomerulus before the urine passes into the renal pelvis


growth, lump, mass