Health dictionary - L

Health dictionary


A ragged wound or cut.


The medical word for voice box – the part of your throat that produces sound.


Doctors make a really small cut on your body but you won't feel anything because you'll be under anaesthetic. They use this cut to put a really tiny camera inside your body in a bendy tube. This allows them to find out what's going on inside you.

Large bowel

This is also called your colon and is where any water from your food is absorbed to form poo.


A machine that produces a bright beam of light. Lasers are used to cut skin and can also shrivel up blood vessels.


Medication taken to stimulate a bowel movement and relieve constipation. In other words, it helps you have a poo.


The part of your eye that lets you focus what you see so it is clear.


A type of cancer that affects your blood cells.


A band of tissue that holds the ends of bone together. You can sprain or tear your ligaments by twisting awkwardly but they can be treated.


The liver is the largest organ in your body. Its job is to produce and keep control of the chemicals circulating in your body, removing any waste products from the blood. In adults, the liver weighs around one kilogram.

Lumbar puncture

A procedure where a needle is inserted in the spaces between the bones in your spine. It's used to get access to your cerebrospinal fluid (CSF) to either take a sample to test for infection, or to give medicines intrathecally.


This is the space inside a tube. In medicine, it's usually used to refer to the inside of a tubular organ, like your intestines, or the inside of a tube to give medicine, like a central line.


You usually have two of these, on either side of your chest inside your ribcage. When you breathe in air, it travels down the windpipe through the bronchi, into your lungs. When you breathe in, your lungs expand, and when you breathe out, they go back to their normal size. Your lungs are full of little bags (alveoli) which remove oxygen from the air we breathe in, and put carbon dioxide into the air we breathe out.


This is a fluid that circulated in the lymphatic system. It's full of lymphocytes – white blood cells which fight infection.

Lymphatic system

This is part of the immune system. Lymphatic vessels drain lymph away from the body and back into the bloodstream.


This is a type of white blood cell that fights infection. There are two types – T cells and B cells. B cells protect against second attacks of infectious diseases like measles.