Definition of "cipher" []

• The mathematical symbol (0) denoting absence of quantity; zero. (noun)
• An Arabic numeral or figure; a number. (noun)
• One having no influence or value; a nonentity. (noun)
• A cryptographic system in which units of plain text of regular length, usually letters, are arbitrarily transposed or substituted according to a predetermined code. (noun)
• The key to such a system. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "And "cipher" is the nom de guerre of Le Chiffre, the numbers-man racketeer of the French Communist Party and perhaps the most odiously sadistic of Fleming's villains."
• "Eyeballing the incomplete key so far, there do seem to be some obvious glyph clusters, and I should note the possibility that solving the substitution cipher is only step one."
• "Put in cipher #2 in slot 1 so you are going to (2,0)."