Cavity
WordNet
noun
(1) (anatomy) a natural hollow or sinus within the body
(2) A sizeable hole (usually in the ground)
"They dug a pit to bury the body"
(3) Soft decayed area in a tooth; progressive decay can lead to the death of a tooth
(4) Space that is surrounded by something
WiktionaryText
Noun
- A hole or hollow depression.
- A hollow area within the body (such as the sinuses).
- A soft area in a decayed tooth.