FF2J Share definition Flag Acronym for "Feel Free To Join". Can be said when going out, playing video games, or other applicable instances. MySpace Bulletin: Going to a movie at 7p, ff2j Xbox Live: m2af, playing Halo 3, ff2j FF2J by Domonic January 7, 2009 0 0 Get merch Get the FF2J mug. Buy Now — $32.95 See more merch
