Throw shade, from urban dictionary: To talk trash about a friend or acquaintance, to publicly denounce or disrespect. When throwing shade, it's immediately obvious to on-lookers that the thrower, and not the throwee, is the bitcy, uncool one. I first learned the term from watching Real Housewives of Atlanta. It's not a phrase I would really use in real life, because people would look at me like I was nuts.