[syn: cryptogram, cryptograph, secret writing]
3.  a device for deciphering codes and ciphers; 
The Collaborative International Dictionary of English v.0.48:
Cryptograph \Cryp"to*graph\ (-gr?f), n. [Gr. krypto`s hidden +
   -graph: cf. F. cryptographe.]
   Cipher; something written in cipher. "Decipherers of
   cryptograph." --J. Earle.
   [1913 Webster]
WordNet (r) 3.0 (2006):
cryptograph
    n 1: a secret method of writing [syn: cipher, cypher,
         cryptograph, secret code]
    2: a piece of writing in code or cipher [syn: cryptogram,
       cryptograph, secret writing]
    3: a device for deciphering codes and ciphers