(business, espionage, military) A name used to clandestinely identify somebody or something, either for military or espionage purposes, or for commercial confidentiality.

(computing) A numeric value or string of such values that triggers a specific command or action to occur, rather than displaying a text character.

A sequence of letters and/or numbers added to a postal address to aid the sorting and delivery of post/mail.

A numeric code generated at regular intervals by a timing system.

Any code whose elements may take one of three values

(computing) The output of a compiler or assembler; it is not necessarily executable directly without linking to other modules

(computer science) A system of instructions and data directly understandable by a computer's central processing unit.

A substitution cipher

(slang, sometimes derogatory) A computer programmer.

Synonym of wall of silence