KNUCKLE

I. noun Etymology: Middle English knokel; akin to Middle High German knöchel ~ Date: 14th century 1. the rounded prominence formed by the ends of the two adjacent bones at a joint, the joint of a ~, a cut of meat consisting of the tarsal or carpal joint with the adjoining flesh, something resembling a ~: as, a. one of the joining parts of a hinge through which a pin or rivet passes, ~ joint , the meeting of two surfaces at a sharp angle (as in a roof), a pivotal point, a set of metal finger rings or guards attached to a transverse piece and worn over the front of the doubled fist for use as a weapon, ~d adjective II. verb (~d; knuckling) Date: 1740 intransitive verb to place the ~s on the ground in shooting a marble, transitive verb to press or rub with the ~s