Word origin Trinidad. Buttiwash is the act of a man licking a
woman's ass. Ordinarily, associated with a horny man so overcome with
joy and excitement from getting a beautiful
woman with a nice ass in bed, that he puts his face right on her bare ass.
Nancy to
Bob: Hi
Bob, whatcha doin buttiwash? I haven't showered in three days.
Bob to Nancy: Don't worry honey, I will clean you right up.