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1.
A Bunto is a very close "brother or sister " but not realated. Very close friends.
Me and my bunto were macin on some biddies yesterday biiiotch.
by Mr. YEA YOUR RIGHT July 12, 2009
 
2.
A Spanish Word For Bitch.Mostly used by spanish/mexican cholos.
You Better Watch Your Fucking Back Bunto!
by Vatos Locos October 11, 2003