fart truster Share definition Flag Someone who trusts a fart and then becomes bitterly disappointed by the messy ramifications. Joan used to be a fart truster, that is until the concept back-fired on her and she shidoobied herself instead. fart truster by Banniflat March 10, 2009 0 0 Get merch Get the fart truster mug. Buy Now — $32.95 See more merch