—n. 1. a hollow in the earth, esp. one opening more or less horizontally into a hill, mountain, etc.
2. a storage cellar, esp. for wine.
3. Eng. Hist.a secession, or a group of seceders, from a political party on some special question.
—v.t. 1. to hollow out.
2. Mining. a. to cause (overlying material) to fall into a stope, sublevel, or the like.
b. to cause (supports, as stulls or sets) to collapse beneath overlying material.
c. to fill (a stope or the like) with caved-in material: sub-level caving.
—v.i. 1. to cave in.
2. cave in, a. to fall in; collapse.
b. to cause to fall in or collapse.
c. Informal.to yield; submit; surrender: The opposition caved in before our superior arguments.