Source : Webster's Revised Unabridged Dictionary (1913)

Crypt \Crypt\ (kr[i^]pt), n. [L. crypta vault, crypt, Gr.
   kry`pth, fr. kry`ptein to hide. See {Grot}, {Grotto}.]
   1. A vault wholly or partly under ground; especially, a vault
      under a church, whether used for burial purposes or for a
      subterranean chapel or oratory.

            Priesthood works out its task age after age, . . .
            treasuring in convents and crypts the few fossils of
            antique learning.                     --Motley.

            My knees are bowed in crypt and shrine. --Tennyson.

   2. (Anat.) A simple gland, glandular cavity, or tube; a
      follicle; as, the crypts of Lieberk["u]hn, the simple
      tubular glands of the small intestines.

Source : WordNet®

crypt
     n : a cellar or vault or underground burial chamber (especially
         beneath a church)

Source : Free On-Line Dictionary of Computing

crypt
     
        {Unix} command to perform {encryption} and {decryption}.