Health dictionary - A

Abdomen

The abdomen is actually just another word for your stomach.

Abscess

A collection of pus, which usually happens as a result of an infection. Pus is made up of old white blood cells and broken down tissue cells. Abscesses can be very painful and may need to be drained.

Acute

If it's acute, it's strong or intense or comes on suddenly.

Adenoids

Lymph nodes at the back of your nose, above your tonsils. If they’re too large and causing breathing problems, you may need to have them removed.

Adolescence

When you’re too old to be a child and not old enough to be an adult. We usually use the word adolescence to describe the time when you’re a teenager.

Adrenal glands

These are part of the endocrine system and secrete hormones. Your adrenal glands are on top of each kidney.

Allergen

Something that cause an allergic reaction.

Allergy

Lots of people have allergies. They're something that your body reacts to, and often include foods and materials that you come into contact with. Usually they are harmless, but for some people they can be much more serious and make them very ill.

Alopecia

This is when you lose some or all of your hair. This can be caused by medicines or it can be due to an autoimmune disease.

Ambulance

The vehicle that brings you to and from hospital. There are two types – one is an emergency response vehicle, which contain all the equipment to look after you immediately after an accident. The other type does not contain so much equipment but takes you to and from hospital appointments.

Anaemia

A condition where your red blood cells cannot carry enough oxygen. It makes you feel tired and you may look pale. There are lots of different types of anaemia – some are more serious than others.

Anaesthetic

If you're under an anaesthetic, you won't feel any pain during a test or an operation. It's a special mixture of drugs, which can be breathed or injected. A general anaesthetic will let you 'sleep' while everything's going on, so you won't feel anything.

Anaesthetist

An anaesthetist is a special doctor who will look will make sure you 'sleep' safely during an operation or test, and make sure that you're OK afterwards.

Analgesia

Another word for pain relief.

Anapens

A trademarked name for an epinephrine autoinjector. It is a pen shaped device that is used to treat severe allergic reactions.

Anaphylaxis

Lots of people have allergies, which means they can't eat certain foods or touch some materials. Anaphylaxis is a severe type of allergic reaction.

Anatomy

The science of where everything is in your body and how it is formed.

Angiogram

This is a special X-ray picture of an artery - that's the vessel that takes blood from your heart and around your body.

Anorexia nervosa

A type of eating disorder, where the person avoids food and eating.

Antenatal

The period of time before a baby is born. For instance, antenatal screening is used to find out if the baby is OK before it is born.

Anterior cruciate ligament (ACL)

One of four major ligaments of the human knee. It is critical to knee stability.

Antibiotics

Bacteria (germs) can sometimes make you ill, and that's where antibiotics come in. Antibiotics are medicines that attack bacteria that are making you feel unwell. Although they hurt the bacteria, they won't hurt you.

Antibody

A substance in your blood that reacts with something you’re allergic to (allergen).

Antihistamines

If you've got an allergy, antihistamines can help to stop a bad reaction. They're usually tablets but sometimes you might be given a syrup, because it is easier to swallow.

Antiseptic

Something that prevents infection. You can get antiseptic mouthwash, antiseptic cream, and antiseptic hand wipes, all of which prevent infection.

Aorta

This is the main artery in your body which carries blood away from your heart.

Apnoea

A condition where you stop breathing – usually only for a few seconds. Some people have apnoea only when they’re asleep.

Appendix

A little tube attached to your large intestine that has no function at all! It’s about 9cm long in adults and doesn’t usually cause any problems, unless it becomes infected – which is called appendicitis.

Arrhythmia

This is when the heart doesn’t beat in a regular way – some people have this all the time, and they need something called a pacemaker to make the heart beat regularly.

Arteries

Our bodies contain lots of blood, which moves around in arteries, veins and capillaries. Arteries carry blood away from the heart to the rest of your body. They are made up of different layers in a tube.

Arthritis

A disease where your joints swell and become stiff and painful. Some people think only old people get arthritis but it can affect young people too!

Aspiration

The removal of a gas or fluid by suction.

Aspirin

A type of pain relief that usually comes in tablets. Aspirin can be dangerous for children under 16 years old, so you should only ever take it if your doctor says its OK.

Asthma

A condition where you feel breathless and wheeze a lot. It’s caused by the passages in your lungs becoming inflamed, but it can be treated using drugs which open up these passages (bronchodilators).

Athlete’s foot

This is a nasty infection you can get between your toes that is caused by a fungus. It’s very contagious so make sure you don’t walk around in bare feet when you’ve got it, and don’t share your shoes with anyone either. It can be treated using creams from your chemist.

Atresia

This means that a passage or canal in the body is closed up at one end instead of being like a tube. There's lots of different types of atresia, which all happened while the baby was developing in the womb.

Atrium

One of the chambers in the heart.

Audiology

The study of hearing.

Audiologist

A person who studies your hearing and can suggest ways of improving it if you have problems.

Autoimmune

This is a kind of disease where the body gets confused and starts attacking itself because it thinks it’s dangerous. For instance, in arthritis, the body identifies the tissue in the joints as being ‘the enemy’ and so attacks them causing damage.

Autophobia

Fear of loneliness, or of being left alone.

Axilla

This is just a word doctors use for your armpit.