What is Bitch Mouth?
1.
A bitch mouth is any guy who who runs his mouth like a little
This is particularly true in the context of gettin pwned (i.e. getting an ass whoopin form you boy in a game of hoops, you whine and complain like a dirty bitch mouth). This word can be used as a direct object noun (i.e. he has a bitch mouth) or as an act (i.e. Every time I kick you ass in poker you act like such a dirty bitch mouth).
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2.
A guy who says he has mad game but when put to the test he doesn't do shit
Joe told us how he was gonna fuck all the bitches at the party but when they came he just sat there and didn't do anything i knew he had bitch mouth all along.