Whenever a guy with a very hard dick, usually foot long (or longer), thrusts his dick into a girl so hard she goes flying into the nearest appliance, such as a wall, tv, window, etc.
Jeff thwamed his long, throbbing, dick into Britney's wet vagina, and she flew out of the nearest window then preceded to crash into the neighbors car.
by spooningyourmum February 25, 2010
Get the Thwammug.