pensioners slap Share definition Flag A poor substitute for a shower when cold water is used to pat under the arms, between the legs and on the face. Did you have a shower this morning? Nah, couldn't be arsed. I just had a pensioners slap. pensioners slap by Chutney Didsby July 24, 2014 0 0 Get merch Get the pensioners slap mug. Buy Now — $32.95 See more merch