Fucked up grill is referencing the situation of one's teeth. There is an erray of grill issues that can earn a person this particular title. examples include but are not limited too

1)Meth teeth: little pointy black nubs, a great example of this look in cinema is the headless horseman character in Sleepy Hollow.
2)Can eat corn on the cob through a picket fence teeth: This is when one tooth is way up front while the one right next to it is far back. This typically continues across the entire grill.
3) Piss poor hygiene teeth: we all know this person. Puffy red gums, bad breath, yellow butter coating on the teeth that are somehow still present.

4) Extra teeth: I know you know what I'm talking about. Above the tooth line of this grill has one to several little bonus teeth perched in the no tooth zone.
"Yo man, that chick would be hot if she didn't have that fucked up grill"
If the grill is severely fucked up the word ass can be added for added drama
"Dude, why didn't you let her blow you?" "Come on man have you seen her fucked up ass grill? I ain't putting my dick in that meat grinder"
by Groovingupslow October 16, 2015
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