boy beater Share definition Flag another term for 'wife beater', more relevant to the gay community. an a-shirt. a tight, ribbed, white, sleeveless tank-top. All Shawn ever wears is jeans and a boy beater. He needs to work on his wardrobe. boy beater by bfrd2 February 24, 2006 0 0 Get merch Get the boy beater mug. Buy Now — $32.95 See more merch