Knockin' Noggins Share definition Flag When one or males make contact with the heads of their penises. Can often be played as a game similar to jousting. Hey man, as long as we have our pants off... We might as well be Knockin' Noggins. Knockin' Noggins by donhonk December 11, 2010 0 0 Get merch Get the Knockin' Noggins mug. Buy Now — $32.95 See more merch