butt leach Share definition Flag Butt leach = co-worker who sucks the bosses ass so hard they resemble a parasite such as a leach. Omg she totally kisses the bosses ass....she is such a butt leach! butt leach by jamieirene January 27, 2014 0 0 Get merch Get the butt leach mug. Buy Now — $32.95 See more merch