badass grinding 

1.) V. When someone gains significantly noticeable levels of badassness (see. take a level in badass) as if almost overnight or within a short period of time. Taken from modern gaming in the styles of herding or grinding to gain experience points to level up multiple levels. It's badass gain on overdrive. Quite simply put, it means when someone takes multiple levels in badassness.

1.) What happened to Bill over the summer? It's like he went from pussy geek to instant badass.

2.) Yeah, I hear he's joined a UFC gym, and has been doing some badass grinding ever since he got pantsed in front of the whole school late last year.

badass grinding by The White Phantom September 22, 2013