a male animal, esp a male deer, antelope, rabbit, or ratSAfr an antelopearchaic a dandyarchaic a man, esp a young and virile, spirited, or impudent man [Old English bucca stag, he-goat]
said of a horse or mule: to spring into the air with the back curved and come down with the forelegs stiff and the head loweredto refuse to agree or cooperate; to balkchiefly NAmer to move or react jerkily verb transto throw (e.g. a rider) by buckingto fight against or refuse to comply with (a system or tendency)
NAmer, Aus, NZ, informal a dollar [perhaps short for buckskin, regarded as a unit of exchange in early N American commerce]
an object formerly used in poker to mark the next player to dealanything that serves as a reminderpass the buck informal to shift a responsibility to somebody elsethe buck stops here informal the responsibility cannot be shifted to somebody else [short for earlier buckhorn knife, used as a buck in poker]