1.) A handsome, strapping man with swagger. 2.) An un-licensed cab driver. 3.) A foreman. 4.) Irish. A man of questionable and eccentric habits. Like that of a rake. 5.) Irish. A young boy or lad. 6.) Canadian. Derog. "A buck" is also a highly offensive racial slur for a native male.
He's a young whipper-snapper or young impressionable male. 2.) Nickname for a man in the urban community circa 1960. "Say, young blood you got a square?" 3.) He's a member of a territorial street gang in California.