den
A small cavern or hollow place in the side of a hill, or among rocks; especially, a cave used by a wild animal for shelter or concealment.
Other meanings
A squalid or wretched place; a haunt.
A comfortable room not used for formal entertaining.
Word history
From Old English "denn".
Where this comes from
This definition is adapted from “den” on Wiktionary, by its contributors, published under CC BY-SA 4.0. This page is published under the same licence.