A piece of shit. Usually dropped on one's head, near or around the facial area.
Dude I totally dropped a Rusty Grenade on this chick last night!
by Jabraham March 13, 2010
The act of defecating and ejaculating into the the palm of ones hand and tossing it over an object (e.g. a book) into the unsuspecting mouth of the target.
I gave Daniel a rusty grenade today while we were playing magic cards. I won the game.
by Daniel07 October 28, 2011
The act of jizzing in ones hand, and then forcibly fisting it into an unsuspecting asshole.
I gave her the rusty grenade last night.. she never saw it coming..
by LoadedBandolier April 26, 2010