F'it Share definition Flag F'it or FIT is a contraction of the words FUCK IT. Used by people who say they don't swear but still use a word to replace the "Swear Word". This bloody computer's playing up again O F'IT F'it by jinker January 25, 2008 0 0 Get merch Get the F'it mug. Buy Now — $32.95 See more merch