Webster's Revised Unabridged Dictionary · 1913

Cipher

Cipher , noun

[Old French cifre zero, French Chiffre figure (compare Sp. cifra, Late Latin cifra), from Arabic cifrun, cafrun, empty, cipher, zero, from cafira to be empty. Compare Zero.]

1.
(Arithmetic) A character [0] which, standing by itself, expresses nothing, but when placed at the right hand of a whole number, increases its value tenfold.
2.
One who, or that which, has no weight or influence.
Here he was a mere cipher. — W. Irving
3.
A character in general, as a figure or letter. [Obsolete]
This wisdom began to be written in ciphers and characters and letters bearing the forms of creatures. — Sir W. Raleigh
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.
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.
His father... engaged him when he was very young to write all his letters to England in cipher. — Bp. Burnet
Collocations (1)
Cipher key , a key to assist in reading writings in cipher.

Cipher , adjective

Of the nature of a cipher; of no weight or influence.
Twelve cipher bishops. — Milton

Cipher , intransitive verb

To use figures in a mathematical process; to do sums in arithmetic.
'T was certain he could write and cipher too. — Goldsmith

Cipher , transitive verb

1.
To write in occult characters.
His notes he ciphered with Greek characters. — Hayward
2.
To get by ciphering; as, to cipher out the answer.
3.
To decipher. [Obsolete] — Shakespeare
4.
To designate by characters. [Obsolete] — Shakespeare