decipher

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decipherment

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• decypher

As decypher, but not retaining the y from the Old French etyma of cipher (cyfre, cyffre); the i spelling tends to be preferred etymologically, being consistent with its cognates, the French déchiffrer and the Italian decifrare, and with their common ancestor, the Medieval Latin cifra, cifera, ciphra. By surface analysis, de- +‎ cipher.

• (UK) IPA^(key): /dɪˈsaɪfə(ɹ)/

• Audio (Southern England):

  (file)

• Rhymes: -aɪfə(ɹ)

decipher (third-person singular simple present deciphers, present participle deciphering, simple past and past participle deciphered)

1. (transitive) To convert a code or cipher to plain text.

   Synonyms: decode, decrypt, uncode (rare)

   Antonyms: encipher, encode, encrypt

   Coordinate terms: recipher, recode

2. (transitive) To read text that is almost illegible or obscure
3. (transitive) To make sense of a complex situation.
   • 1834, L[etitia] E[lizabeth] L[andon], chapter II, in Francesca Carrara. […], volume II, London: Richard Bentley, […], (successor to Henry Colburn), →OCLC, page 13:

     Truly, we need human infirmity to teach us human nature, and that to Louis had been as a sealed book; he had only seen the coloured and gilded outside: too late he had to decipher the rough and gloomy page within.

4. (transitive) To find a solution to a problem.

decipher (plural deciphers)

1. A decipherment; a decoding.
   • 1837, Arthur Wellesley Duke of Wellington, John Gurwood, The Dispatches of Field Marshall the Duke of Wellington, K.G.:

     I enclose a letter which I received yesterday evening from the Marques de Monsalud, containing the decipher of a letter from the King to the Comte d'Erlon. I wish that the Marques had sent the ciphered letter here […]

• ciphered