Boyd’s Bible Dictionary:
(hollow). Used for storage houses, dwellings, hiding and burial places (Gen. 19:30; Josh. 10:16; Judg. 6:2; 1 Sam. 13:6; 22:1; 24:3; 2 Sam. 23:13; 1 Kings 18:4; Heb. 11:38).
Concise Bible Dictionary:
Palestine is remarkable for its number of caves, some of which are of great extent. David and his followers were in a cave in the wilderness of En-gedi, so extensive that they could hide themselves, though Saul came into the same cave (1 Sam. 24:1-8; compare Heb. 11:38). The Adullam cave and others also are of note in the Old Testament The tomb of Lazarus was a cave (John 11:38).
Strong’s Dictionary of Greek Words:
Meaning:
probably from 3700; a hole (as if for light), i.e. cavern; by analogy, a spring (of water)