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1399, from M.L. cifra, from Arabic sifr "zero," lit. "empty, nothing," from safara "to be empty," loan-transl. of Skt. sunya-s "empty." Came to Europe with Arabic numerals. Original meaning "zero," then "any numeral," then (first in Fr. and It.) "coded message" (first attested in Eng. 1528), since early codes often substituted numbers for letters. The verb meaning "to do arithmetic (with Arabic numerals) first attested 1530.