What is "Y.B.Y.S.A.?" No, it isn't pronounced "yuh-bee-suh," it's a popular expression in some areas. It means "You Bet Your Sweet A__," but we'll let you put two and two together. Basically, "Y.B.Y.S.A." expresses a certain sentiment directed toward an opposing team. This t-shirt has printed initials on the chest, with the full expression printed on the back. Cotton/polyester blend material.