1. A localized collection of pus in part of the body, formed by tissue disintegration and surrounded by inflamed area tissue: Shirley had an abscess in her gums that caused her entire mouth to hurt.

The dentist was gentle while he was cleaning out the abscess in Jeffery's wisdom tooth.

2. A circumscribed collection of pus usually caused by microorganisms: The doctor decided to lance the abscess on Ann’s leg so the pus could drain.

In the hospital Joan had several abscesses on her body as a result of lying in the same position for too long.

Abscesses can occur anywhere in the body, in hard or soft tissue, organs, or confined spaces; and because of their fluid content, abscesses can assume various shapes.

The internal pressure of abscesses can cause compression and displacement of surrounding tissue, resulting in pain, however it is part of the body's natural defense mechanism because it localizes infection to prevent the spread of bacteria.

3. Etymology: from Latin abscessus, "an abscess"; literally, "a going away," from the stem of abscedere, "withdraw"; from ab-, "away" + cedere, "to go". The idea was that humors "go from" the body through the pus in the swelling.