[1] : The Collaborative International Dictionary of English v.0.48

cipher \ci"pher\, n. of. cifre zero, f. chiffre figure cf.
   sp.cifra, ll. cifra, fr. ar. ,cifrun, ,cafrun, empty,
   cipher, zero, fr. ,cafira to be empty. cf. zero.
   1913 webster
   1. arith. a character 0 which, standing by itself,
      expresses nothing, but when placed at the right hand of a
      whole number, increases its value tenfold.
      1913 webster

   2. one who, or that which, has no weight or influence.
      1913 webster

            here he was a mere cipher.            --w. irving.
      1913 webster

   3. a character in general, as a figure or letter. obs.
      1913 webster

            this wisdom began to be written in ciphers and
            characters and letters bearing the forms of
            creatures.                            --sir w.
                                                  raleigh.
      1913 webster

   4. a combination or interweaving of letters, as the initials
      of a name; a device; a monogram; as, a painter's cipher,
      an engraver's cipher, etc. the cut represents the initials
      n. w.
      1913 webster

   5. a private alphabet, system of characters, or other mode of
      writing, contrived for the safe transmission of secrets;
      also, a writing in such characters.
      1913 webster

            his father . . . engaged him when he was very young
            to write all his letters to england in cipher. --bp.
                                                  burnet.
      1913 webster

   cipher key, a key to assist in reading writings in cipher.
      1913 webster
see also:
zero cipher key 

Cipher >> C Words
Cipher, definition of term: Cipher
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Church Key >> C Words
Church Key, definition of term: Church Key
church+key_pag1.html