| Term | Definition |
|---|---|
| Ulcer |
A break or deep sore in the skin. Germs can enter an ulcer and may be hard to heal. |
| Urea |
One of the chief waste products of the body. When the body breaks down food, it uses what it needs and throws the rest away as waste. The kidneys flush the waste from the body in the form of urea, which is in the urine. |