the moment at which someone (or something) who has been consistently dependable suddenly collapses or disintegrates, due to age or any other factor
this phrase was popularized (and perhaps created) by Bill Simmons of ESPN as a candidate to replace jump the shark, it references the decline of the NBA's Gary Payton which became shockingly apparent in the 2004 NBA playoffs
Before marrying my girlfriend, my intuitions warned me that her libido eventually will go GP on us.
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.
FRIEND A: "Did you just take a stealthie of me?"
FRIEND B (turning phone around): "no I was just using snapchat's new filter, see?"