Guinness Necktie Share definition Flag The contents of a pint of guinness that did not make it down your throat during a chug (irish car bomb) and ended up down the front of your shirt. "I don't care how fast you bomb it, if you end up with a guinness necktie, you lose." Guinness Necktie by elw31 March 31, 2008 Get the Guinness Necktie mug.