Crypt

Webster's Dictionary of the English Language

·noun A simple gland, glandular cavity, or tube; a follicle; as, the crypts of Lieberk/hn, the simple tubular glands of the small intestines.

II. Crypt ·noun 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.