BTS is the initial of the group's Korean name "Bang Tan Sonyondan (방탄소년단 in the Korean alphabet 'hangul')." "Bang (방) tan (탄)" means "bullet-proof." "Sonyon (소년) means "boy" and "dan (단)" means "corp" or "scout," making "sonyondan (소년단)" together mean "boyscouts." So their name BTS means the "Bullet-proof Boyscouts."