agnostic Share definition Flag agnostic (àg-nòs´tîk) noun:an atheist trying to hedge his bet. He's an agnostic. He doesn't know if there is a god, but he's trying to cover his bet. agnostic by skyweeder October 10, 2009 0 0 Get merch Get the agnostic mug. Buy Now — $32.95 See more merch