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2.
Abbreviation for "the fuck if I know".
I think he was in a bad mood because he broke up with his girlfreind or something, but TFIIK.
by ArguableHappymaster June 03, 2011
 
1.
short for "the fuck if i know"
TEXT CHAT:
Bob: where did joe go?
John: tfiik
by gamewin1 August 13, 2011