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English definition of “cipher”


noun [C or U] (SECRET LANGUAGE) (also cypher)     /ˈsaɪ.fər/ US  /-fɚ/
a system of writing that prevents most people from understanding the message: The message was written in cipher. → Synonym code nounCodes and decodingSigns, signals and symbols
(Definition of cipher noun (SECRET LANGUAGE) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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