BFOT Share definition Flag Big Fan Of That (acronym). A description of how someone feels if they sincerely like something. A supporter of something appealing. Bryan: Yo! Bill did you see the legs on the new girl in accounting? Bill: Oh yeah! I'm a BFOT! BFOT by diegodiegodiego February 1, 2009 0 0 Get merch Get the BFOT mug. Buy Now — $32.95 See more merch