Top definition
when u unleash a massive load of fuck your shit up all over some stupid asshole who is trying to mess with you in any way.
you have just been killed and tea baged in halo 3 on xbox live.
you:"what the fuck was that, did that huge fagot just teabag me? oh hes fuckin dead im gonna unleash some GRUNDLEMAYHEM on his stupid ass."
you then go on to dom the shit out of him killing him like 18 times making him quit halo3 forever and put his family in shame for many years
by wow hes a faggot January 10, 2010
Get the mug
Get a GRUNDLEMAYHEM mug for your daughter-in-law Helena.