A reflexive physical manifestation of the base emotional reaction that occurs when one encounters something they find decidedly offensive and/or insulting at either an instinctual or intellectual level.
The feeling you get when something is so incredibly embarassing and/or retarded, you have to avoid making contact or avert your attention with it or else taking the risk of feeling like a total loser-douche.
From some shitty teen movie, popularized by the latenight Washington Area radio show "The Hideout Featuring El Jefe and J Dubs"