cipher noun 1 the information may be given in cipher: code, secret writing; coded message, cryptograph, cryptogram. 2 he has spent most of his working life as a cipher: nobody, nonentity, nothing, non-person, unimportant person, person of no account. ANTONYMS celebrity 3 a row of ciphers: zero, nought, nil, 0; archaic naught. 4 Arabic ciphers: numeral, number, integer, figure, digit; character, symbol, sign.