After a long day of hot sweaty work, putting your hand down your pants and filling your palm w/sweat from your scrotum. Then with said sweat slapping somebody dear to you.
Yo man, I just got off work and I went up to Andrew and gave him a ScrotumSlap.
A male dips their scrotum in tea and then furiously jabs their partner in the face with it. Then they stuff it in their partner's mouth cleaning the tea off of its surface. Then the male backs as far as they can go in the room then charges the women with their sack in one hand and facing outwards. When in contact with the women he tackles her and then begins to slap her across the face with his dry scrotum.
When a man inserts his penis into the rectum of another gentleman, the two scrotums (scrota?) come into contact. As the intercourse intensifies, the scrotums will make a distinctive slapping sound. Umm, at least that's what I've heard. I read about it once, honestly.
Buck: So are you and Carl dating or what?
Ned: Nah, we justslapped scrotums a few times.
when you're holding up your phone and making faces at it, as though you are taking a selfie, but you're really taking a picture of the person across from you or the wall or anything else that seems interesting but you don't want to be caught dead taking a picture of.
This action is often made more convincing by wiggling the eyebrows or opening the mouth, to pretend you're trying to get a Snapchat filter to work.