g-nob Share definition Flag Bong. Derived from bong ('bon-g' specifically) in reverse, pronounced 'gee-knob'. "Sorry I bailed last night, hit the g-nob a bit too hard." g-nob by Hawt S September 8, 2005 0 0 Get merch Get the g-nob mug. Buy Now — $32.95 See more merch