rowdy n.

"a rough, quarrelsome person," 1808, originally "lawless backwoodsman," "Of American, but otherwise quite obscure, origin" [OED]. Perhaps from row (n.2) "noisy commotion" (itself of uncertain origin). The adjective, "having the manners of or conducting oneself like a rowdy, rough and noisy," is attested by 1819. Related: Rowdily; rowdiness; rowdyism.