to agree to a (usually coinflip) prop bet but back out at the last moment.
anyone wanna flip for $100? no grimstarring !
by CaptainBusto September 30, 2006
1 more definition
grimstarr, grimmed. Of pizza faced nature. Male with erect penis not exceeding 2 inches. Genenral ghey activites. Douchebag.
so then we went to 'do-it' and i looked down and was like...what a grimstarr. see that dudes face...its like the moons fucking surface..what a grimstarr. that dude grimmed me off..what a grimstarr
by stan darsh August 18, 2007