Back Beaver Share definition Flag The word used to describe hair on a girls lower back (often on Mexican women) Dude, I went to sneak a peak at that chicks thongage but all I saw was her disgusting and hairy back beaver! Back Beaver by koolaidman21 July 25, 2008 0 0 Get merch Get the Back Beaver mug. Buy Now — $32.95 See more merch