It is an operating system that is disliked by the creatorof it(or CEO of the Company that released it), or the users. For example when Bill gates was interviewed and pointed out that he doesn't like vista.
"Man, after Bill Gates said he doesn't like Vista, it made me feel like I'm using a piece-of-crap-OS!"
by Kevinthetrooper June 23, 2008
buy the domain for your pet blog