Small plug of faecal matter that is expelled with ejaculant onto a porn-star's back at the "climax" of a poo-tube segment in a movie. May be seen regularly in either straight or gay porn. Both irritating and unsightly, the winnet is a real mood killer.... hence, its dual use in describing a turd, weasel, arsehole BMW driver, or other annoying fool.
Eddie: "I can't believe it.... all I asked him for was a couple of hours off to take my kid to the hospital!"
Mike: "Don't sweat it Eddie, the guy is just a winnet. We will work something out for you."