The third person involved in a threesome with a couple. A sexual third wheel usually a stranger or acquaintance.
My girlfriend and I invited the hot chick from the airport to be our guest star Friday night and she was a total freak.
by Mr Trev Trev April 29, 2010
An actor, actress or some other form of entertainer who makes guest apperances on a several television shows during a period of time in which they do not have anything else going on in their career-this usually occurs when one's career has reached a dead end
That Victoria Justice just keeps popping up all over Nicelodeon's other TV shows-she's such a Guest Star Whore
by repoed2 January 24, 2010