1375-1425 for sense “grotto”; 1555-65 for current senses; late Middle Englishcripte < Latincrypta < Greekkryptḗ hidden place, noun use of feminine of kryptós hidden, verbid of krýptein to hide; replacing earlier crypta < Latin, as above
early 15c., "grotto, cavern," from L. crypta "vault, cavern," from Gk. krypte, fem. of kryptos "hidden," from kryptein "to hide." Meaning "underground burial vault or chapel in a church" first attested 1789.