:SO: /S-O/ n. 1. (also `S.O.') Abbrev. for Significant
Other, almost invariably written abbreviated and pronounced
/S-O/ by hackers. Used to refer to one's primary
relationship, esp. a live-in to whom one is not married. See
{MOTAS}, {MOTOS}, {MOTSS}. 2. The Shift Out control
character in ASCII (Control-N, 0001110).
-- The AI Hackers Dictionary
EOF /E-O-F/ n.
[abbreviation, `End Of File']
1. [techspeak] The out-of-band value returned by C's
sequential character-input functions (and their equivalents in
other environments) when end of file has been reached....