An epidemic that is spreading across private schools across America. Rich fuckups that feel the need to protect their necks are especially likely to contract Collar Popping Syndrome, or C.P.S. The disease involves a person wearing a button down shirt with the collar flicked up. Not only is this hazardous to personal health but it is also a mortal sin. Anyone, preppy or not, who catches C.P.S. will surely be damned for it.
Usually when one pinches the sides of your collar, usually on a polo or dress-shirt. You pinch the sides, and pull them up in self appraisal. It's a way of saying to the world, "look at how great I am". Almost exclusively male.
Usually when the boy or girl unfolds the collar of a polo so that it stands straight up around the neck. It's supposed to be 'cool', but you can sometimes come off looking like Batman.
For gangstas; "You were popping your collar when I told you how sharp you looked in that velour suit."
For preps; "Nick was popping his collar in class today. At first I thought his ears were cold, but then I realized he thought it was 'cool'."
"Now every since I could remember I been poppin my collar
Every since I could remember I been working this hoes
And they betta put my money in my hand" -- Three 6 Mafia
That's urban slang for pimpin', stunnin', or lookin' fly made popular by the rap group 3 six mafia. Or if someone wants their respect or recognition for doing something. Kind of like when the Fonze on 'Happy Days' use to turn his collar up to be cool.