a homosexual reference in the African American "down low" community, originally coined by Mike Jones, used to describe a handjob that is delivered surrepticiopusly under the table at a night club by another man who is pretending to "mack" on some hoes.
Origin: The Bay Area
Part of Speech: Proposition
Gay Black Man: "yo mayne, you Grippin grain??"
Me: "Hell naw, my tree don't fall that way!"