1. something utterly distasteful and/or unfair
2. anything that is overly grimey
student: bitch, that is mad grimes
2. If a referee was to call pushing while there is clearly no physical contact, on may exlaim, "WHAT? ARE YOU KIDDING? MAD GRIMES"
3. Aw man today i had to be up for a soccer game after consuming massive quantities of alcohol, so mad grimes.