n. & v.
n. 1 a large hollow in the side of a cliff, hill, etc., or underground. 2 Brit. hist. a dissident political group.
v.intr. explore caves, esp. interconnecting or underground. cave-bear an extinct kind of large bear, whose bones have been found in caves. cave-dweller = CAVEMAN. cave in 1 a (of a wall, earth over a hollow, etc.) subside, collapse. b cause (a wall, earth, etc.) to do this. 2 yield or submit under pressure; give up. cave-in n. a collapse, submission, etc. cavelike adj. caver n.
[ ME f. OF f. L cava f. cavus hollow: cave in prob. f. E. Anglian dial. calve in ]