Double Pinch 

A maneuver employed during urination when one realizes, in midstream, that a bowel movement is also needed. The first pinch of the penis cuts off the flow while the pants are unbuckled and dropped to the floor. The second, or the “handoff” pinch occurs after reaching inside the briefs with the opposite hand to continue the pinch, so the briefs can be lowered without incident and a commode employed without delay.

Todd: “Damn!”
Paul (pissing at the adjacent urinal): “What’s the matter?

Todd: “I gotta take a shit right now!”
Paul: Do a Double Pinch. The stall’s empty behind us!”

Double Pinch by OneStarGator November 6, 2017

Double Punching 

Confidently delivering the punchline of a joke, which you don't realise somebody else has already delivered in a more subtle manner.

Kim: I feel really fat
Jim: I can see why
Sim: Yeah. That's because you are really fat. ZING
Jim: Sim fails. Double punching!

Double Punching by sarcasmis September 5, 2011