1. When you cum on a swing-able object(like a rope) and you swing it around making the cum shoot out in many different directions, therefore making the area you cumcoptered in (such as a room)randomly stained with your sperm. Usually done in other people's houses as a prank or if you really hate them.
Example: Person 1: yo Jason, im going to prank James by pulling a Cumcopter in his room.
Person 2: Good idea Jimmy, i fuken hate that kid, that prank would deserve a roflcopter.
Person 1: I get it they both end in copter... anyways can i borrow a swinging like object so i can do it?
Person 2: ya sure let me go get my sisters skip-it.