A double whammy is two or more girls with lesbian tendencys who express their homosexual needs by hooking up with the same guy at the same time. these girls are most likely to be thought of as best friends and hipster whores that no one likes. a double whammy usually is attracted to the jock but only usually gets desperate losers, and other non significant beings.
guy: hook up with me, both of you. * being ironic*
double whammys: sure *serious*