[Usenet, particularly rec.arts.sf.written.robert-jordan] Abbrev. of ‘tangent’, as in “off on a tangent”, and synonym for OT. A number of hacker-humor synonyms are used for TAN in some newsgroups. Instances such as BEIGE, OFF-WHITE, BROWNISH-GRAY, and LIGHT BROWN have been observed. It is generally understood on newsgroups with this convention that any color descriptor is a TAN synonym if (a) used as the first word(s) of the topic of a Usenet post, (b) written in ALL CAPS, and (c) followed immediately by a colon. Usage: “OFF-WHITE: 2000 Presidential candidates” on an SF newsgroup.