n. A hidden or secret recess; a subterranean cell or cave, especially one constructed or used for the interment of bodies, as in the catacombs.n. A part of an ecclesiastical building, as a cathedral, church, etc., below the chief floor, commonly set apart for monumental purposes, and sometimes used as a chapel or a shrine.n. In anatomy, a follicle; a small simple tubular or saccular secretory pit; a small glandular cavity: as, a mucous crypt (a follicular secretory pit in mucous membrane). See follicle. Also crypta.