I know this word only in numerical and cryptographic contexts. Apparently there are others!
“n.
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.
2. One who, or that which, has no weight or influence.
Here he was a mere cipher. --W.
3. A character in general, as a figure or letter. [Obs.]
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
Cipher key, a key to assist in reading writings in cipher.” (dictionary.com, Webster’s).
11/29/08 Washington Post review, “Faust Sells Itself Short at the Multiplex” by Anne Midgette, about the Met’s production and HD broadcast of Berlioz’ “La Damnation de Faust.”
“…As for John Relyea, he offered, in the house, a variant on the tried-and-true devil shtick that opera-goers have seen countless times before, in a voice that is competent enough, but expressively a cipher; the camera allowed it to appear as if something special was going on.…”
Recently I enjoyed the Met’s HD broadcast of “La Damnation de Faust” at my local theater. I read, with interest, the Washington Post critic’s review which runs both hot and cold, as does my opinion of her review. She makes some points with which I agree, and some I don’t. When she likens the baritone to a cipher, however, I’m curious.