undeciphered

/ˌʌndɪˈsaɪfərd/
adjective
  1. Not having been read, interpreted, or understood, especially of a code, writing, or language.
    • The undeciphered script from the ancient civilization remains a mystery to linguists.
    • The scientist spent years trying to understand the undeciphered symbols on the tablet.
    • Many undeciphered messages from the war are still stored in archives.
Antonyms
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