cryptogram

/ˈkrɪptəˌɡræm/
noun
  1. A piece of writing in code or cipher; a message that is written in a secret way.
    • The spy left a cryptogram on the table for his contact to decode.
    • She solved the cryptogram by matching letters to find the original words.
    • In the puzzle book, each cryptogram had a hidden message about history.
Synonyms
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