F.B.I Share definition Flag F.B.I is an anagram for fucking bitched it, a term used for passing a test or doing good on a assignment. that last test, I F.B.I.she F.B.I when we had sex F.B.I by fukut47a June 1, 2011 0 0 Get merch Get the F.B.I mug. Buy Now — $32.95 See more merch