Ex. 1: When someone hides the a closet of a room where two people are having sex, and you run out, flapping your arms and squawking.
Ex. 2: Guy 1: Hey, what are you doing this weekend?
Guy 2: Oh, I'm gunna go seagling!
(Seagling) Two people you know are going to have sex in a room, so you go hide in the closet. When they are busy, run out of the closet flapping your arms like a bird and squawk like a seagull.