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1 definition by Squishy Carpet

Form of online speak used in a forum, short for "Ban This Idiot". Used when a poster on a forum talks or behaves in such a manner that he or she merits being banned to prevent other users from having to put up with such idiocy again.
Poster 1: hey u all sux so much why u use this lame forum?

Poster 2: BTI
by Squishy Carpet February 06, 2006