1650s, "art of writing in secret characters," from French cryptographie or directly from Modern Latin cryptographia, from Greek kryptos "hidden" (see crypt) + graphia (see -graphy). Related: Cryptographic; cryptographer.
early 15c., cripte, "grotto, cavern," from Latin crypta "vault, cavern," from Greek krypte "a vault, crypt" (short for krypte kamara "hidden vault"), fem. of kryptos "hidden," verbal adjective from kryptein "to hide," which is of uncertain origin. Comparison has been made to Old Church Slavonic kryjo, kryti "to hide," Lithuanian kráuti "to pile up." Beekes writes that krypto "is formally and semantically reminiscent of [kalypto]; the verbs may have influenced each other." For this, see calypto-. But he adds, "However, since there is no good IE etymology, the word could be Pre-Greek." Meaning "underground burial vault or chapel in a church" is attested by 1789.
word-forming element meaning "process of writing or recording" or "a writing, recording, or description" (in modern use especially in forming names of descriptive sciences), from French or German -graphie, from Greek -graphia "description of," used in abstract nouns from graphein "write, express by written characters," earlier "to draw, represent by lines drawn," originally "to scrape, scratch" (on clay tablets with a stylus), from PIE root *gerbh- "to scratch, carve" (see carve).
<a href="https://www.etymonline.com/word/cryptography">Etymology of cryptography by etymonline</a>
Harper, D. (n.d.). Etymology of cryptography. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/cryptography