Definition of CIPHER


CIPHER

An arithmetical character, used for numerical notation. Vide
Figures, and 13 Vin. Ab. 210; 18 Eng. C. L. R. 95; 1 Ch. Cr. Law, 176.

2. By cipher is also understood a mode of secret writing. Public ministers
and other public agents frequently use ciphers in their correspondence,
and it is sometimes very useful so to correspond in times of war. A key
is given to each minister before his departure, namely, the cipher for writing
ciphers, (chiffre chiffrant,) and the cipher for deciphering (chiffre dechiffrant.)
Besides these, it is usual to give him a common cipher, (chiffre banal,)
-which is known to all the ministers of the same power, who occasionally
use it in their correspondence with each other.

3. When it is suspected that, a cipher becomes known to the cabinet where
the minister is residing, recourse is had to a preconcerted sign in order
to annul, entirely or in part, what has been written in cipher, or rather
to indicate that the contents are to be understood in an inverted or contrary
sense. A cipher of reserve is also employed in extraordinary cases.

Source: Bouviers Law Dictionary 1856 Edition

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z