cryptogram

noun

1. Encrypted text.

   “It's a big help in solving cryptograms if you know how a cryptogram is constructed. The constructor normally uses two alphabets, one for plaintext, one for the substitute cipher letters.”

   “To anyone who does not know the key, the five characters of the cryptogram are different but the genuine receiver is in no danger of confusion.”

   “Indeed, Willaert was unable to read Charles's musical notation because it was actually a musical cryptogram passing for a madrigal, making absolutely no sense to a mere musician's naked eye, despite his towering talent.”

2. A type of word puzzle in which text encoded by a simple cipher is to be decoded.

   “You already know this if you are an amateur codebreaker. On the comics pages of many newspapers, you will find a little puzzle known as a cryptogram. It's usually a famous quotation that has been encrypted in a very straightforward way […]”