A celebritory dance in which an individual, usually a women, excitedly makes handjob motions to their left and right simultaneously, giving the appearance of wacking two guys off on either side of them
When Sally won the showcase showdown she cried with joy while vigorously doing the double fistedjackoff.
The term that is used for someone willing to take the seat of a (usually) retarded person who calls "shotgun" in an attempt to obtain the front seat of a vehicle. However this must be said within a split second subsequently after the first person calls shotgun.