Wanting nothing to do with someone, whether as a friend/acquaintance or more. Can be abbreviated as "idfwy" or "idfwu". Gained popularity from Big Sean's song. Not to be confused with the sexual meaning of "fucking someone".
Kacey: Hey why don't we invite Lisa to the party?
Marissa: Hell no. I don't fuck with her, she's annoying
A usual response to the question "Wassup can a loc come up in your crib?"
Saying that you will see he who questions you at your place of work, on top of this we can imply that the two people conversing are from the same place of work