the quick flick of one's fingers making contact with another's ballsack, causing a delayed, but tremendous pain in the lower stomach region of one's body.
A hypothetical situation in which a large ring of gay men engaging in anal sex perform Newton's balls, creating a chain reaction that, with a little effort, can continue indefinitely around the circle like a Mexican Wave around a sporting field. There are no recorded occurrences of this.
'I started a Mexican Sacktap but it didn't make it around the circle because Bastian wasn't thrusting in time.'
When an individual is shot directly in the testicles with a rubber bullet from a 12-gauge shotgun while bent over so that the scrotum is in the outstretched and dangling position.