Slang originating from southern Iowa meaning to jump someone with one or more accomplices and then kicking or smushing your
foot onto their
mouth/
teeth as hard as possible as the other person(s) holds them down.
Person 1: Bro, did you hear about
Jack and
Haley graining
Josh yesterday?
Person 2: Yeah, I heard he won't be able to speak normally ever again, dude.