cipheryoudaoicibaDictYouDict[cipher 词源字典]
cipher: [14] The central meaning of cipher is ‘zero’ (a word to which it is related); its use since the 16th century in connection with encrypted communications derives from the fact that in their earliest forms such codes usually consisted of numbers representing letters, and cipher had by then broadened in use from ‘nought’ to ‘any numeral’. It entered English through Old French cifre, which came via medieval Latin cifra from Arabic sifr (source of English zero); this was a nominal use of an adjective meaning ‘empty’.
=> zero[cipher etymology, cipher origin, 英语词源]
cipher (n.)youdaoicibaDictYouDict
late 14c., "arithmetical symbol for zero," from Old French cifre "nought, zero," Medieval Latin cifra, with Spanish and Italian cifra, ultimately from Arabic sifr "zero," literally "empty, nothing," from safara "to be empty;" loan-translation of Sanskrit sunya-s "empty." The word came to Europe with Arabic numerals. Originally in English "zero," then "any numeral" (early 15c.), then (first in French and Italian) "secret way of writing; coded message" (a sense first attested in English 1520s), because early codes often substituted numbers for letters. Klein says Modern French chiffre is from Italian cifra.
cipher (v.)youdaoicibaDictYouDict
"to do arithmetic" (with Arabic numerals), 1520s, from cipher (n.). Meaning "to write in code" is from 1560s. Related: Ciphered; ciphering.