noun

1. The most essential part; the main idea or substance (of a longer or more complicated matter); the crux of a matter; the pith.

2. The essential ground for action in a suit, without which there is no cause of action.

3. Resting place (especially of animals), lodging.

Synonyms: gravamen, crux, quintessence, lair

verb

1. To summarize, to extract and present the most important parts of.