When a nude male, vigorously hip thrusts forward and back. His semi-hard penis loudly,
"slaps" their lower under belly.
This is usually accompanied by howling, hooting and a wildly contorted set face.
It is very animalistic.
When Jack got out of the shower saw his mate and started pork slapping. She got wet from 3 feet away.
Eye slap... verb, to roll your eyes in disgust at someone
Some one rolls their eyes at you in disgust and you ask... Did you just eye slap me?