1) A sleeveless, tight fitted, ribbed tank top for women, typically but not always white. Female fashion equivalent of the more commonly referred to wife beater article of clothing for men. Also known as a boy-beater.

2) A woman who beats her boyfriend.
1) Underneath her jacket, she wore a tight, white boyfriend-beater.

2) I heard that woman is a boyfriend-beater.
by Banjo_oz May 17, 2007
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