Andrzej Dabrowa, Ph.D.
18. Glossary and abbreviations
The following is a list of terms used commonly in the signal intelligence community.
| Abwehr | secret intelligence service of the German High Command |
| Banburisimus | a method of attacking daily naval Enigma keys using perforated sheets made at Banbury (see sheets made by H. Zygalski) |
| Bomba | electro-mechanical machine developed by the Polish cryptographers before WW2 and used to break Enigma settings. It consisted of six Enigmas geared and wired together |
| Bombe | electro-mechanical machine developed by the British cryptographers to break the daily Enigma settings |
| Cillies/sillies | procedural error made by Enigma
operators before sending a message combining (1) a recognisable instead of random choice of message settings and (2) failure to alter the wheel positions much or at all |
| Cipher | substitution of letters or numbers for the plain text message in order to hide the true letters |
| Code | substitution of groups of two or more letters or numbers for the letters, numbers, words, phrases etc in the message to make them compatible with the transmission system |
| Crib | the guessed plain language German text of a message which matched up with a stretch of cipher text |
| Code book | book in two volumes, each arranged in alphabetical order; one for encrypting the plain text and the other for decrypting the encrypted text |
| Code breaker | someone who breaks an enemy code (cipher) system |
| Cryptoanalysis | the technique of breaking codes or ciphers |
| Cryptogram | a coded or encrypted message |
| Decrypt/decode | transform encrypted/encoded text into plain text |
| Discriminant | a group of three letters specifying which key is to be used for Enigma setting |
| Encrypt/encode | transform plain text into an encrypted/encoded text |
| Enigma | the cipher machine used, in various forms, for most communications by the German armed services and several government departments |
| CG&CS | Government Code and Cipher School; often used as a cover name for the decrypting organisation |
| Herivel tip | a particular chance that a lazy or incompetent Enigma operator, after selecting the wheels, wheel order, and wheel settings as specified by the procedure might leave them in (or near) that position instead of turning them to a random setting |
| Hut | housing at Bletchley Park; most of the early work was done in "temporary" huts to which particular sections were assigned. This designation became a cover-name and moved with the sections when they relocated to the solidly built new blocks |
| Indicator | the letters included in the encrypted/encoded message which indicate to the recipient the equipment setting |
| Key | machine set-up used in common by a group of Enigma users |
| Setting | the positions to which the variable elements in Enigma machine were set. These included selection, of wheels, wheel order, wheel position and plug-board connections |
| SLU | Special Liaison Unit responsible for the distribution of ULTRA intelligence |
| Stecker | the plug board on an Enigma, used to scramble the identity of letters before and after passing through the Enigma rotors |
| ULTRA | British cover name for all high grade intelligence derived from many sources, including Enigma |
| W/T | wireless telegraphy |
| Y | interception of radio signals and the decryption of low and medium level codes and ciphers |
(c) 2003 A R Dabrowa