Leyden Slap Share definition Flag The act of being slapped back and forth in the face by a pair of breasts, preferably large. I wanted a hand job, but all she gave me was a Leyden Slap. Can't complain though. Leyden Slap by The Basement Hunter March 20, 2010 0 0 Get merch Get the Leyden Slap mug. Buy Now — $32.95 See more merch