Baby Fish Mouth Share definition Flag Used to describe when a Girl has a set of those puckered up lips and it looks like they are too small to give any head. Damn! That girl you were talking to was fine but it looks like she's got the Baby fish mouth. Baby Fish Mouth by ZZZSpidey December 28, 2006 0 0 Get merch Get the Baby Fish Mouth mug. Buy Now — $32.95 See more merch