The Bletchley Park 1944 Cryptographic Dictionary formatted by Tony ...

The Bletchley Park 1944 Cryptographic Dictionary formatted by Tony Sale (c) 2001
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CILLI. v. (continued)
2. (of an Enigma message). To have its true setting revealed (sc.
as a keyboard, pronounceable, or the like) by back-calculation
from a cilli.
CILLIER :
1. An Enigma encipherer who tends to use cillies.
2. An Enigma key on which cillies tend to occur.
CIPHER :
1. Any system whereby the individual letters, figures, punctuation
marks, etc., of plain language, or the individual letters, figures
or other symbols of an encoded message are rearranged among themselves
( transposition ) or with an admixture of other figures or
letters ( dummies) or replaced by different letters, figures, etc.
(substitution ), with a view to making the message unintelligible
to anyone not in authorised possession of the knowledge or
apparatus necessary to reverse the systematic process and so
restore the order or letters, figures, etc. of the original
plain language or encoded message.
2. A series of unintelligible letters, figures, and/or other
symbols etc. produced from plain language or code by the above
means; an enciphered message; a cryptogram.
3. (misused for). An encoded message.
CIPHER ALPHABET :
The letters of the alphabet and/or other symbols used, if any,
arranged in the order in which they are substituted for the letters
of the clear alphabet (a, b, c, etc.) for a particular key-letter,
usually with the clear alphabet written alongside.
CIPHER-BOX :
A Playfair square.
CIPHER-DISC :
A ciphering device consisting of two concentric discs of unequal size
(the smaller rotating on the larger) each being divided usually into
26 equal sectors in which the letters of the alphabet are inscribed.
The smaller disc has the clear alphabet, usually in alphabetical order,
on it, and the larger disc the cipher alphabet, usually in hatted
order; but the orders may be alphabetical on both or hatted on both.
Each of the 26 different relative positions of the discs gives a
different cipher alphabet.
CIPHER-GROUP :
1. A letter-and/or figure-group in a cipher message.
2. (misused for code-group)