The kneejoint, or middle joint, of either leg of a
quadruped, especially of a calf; – formerly used of the kneejoint of a
human being.

The joint of a plant.

The joining pars of a hinge through which the pin or rivet
passes; a knuckle joint.

A convex portion of a vessel’s figure where a sudden
change of shape occurs, as in a canal boat, where a nearly vertical
side joins a nearly flat bottom.

A contrivance, usually of brass or iron, and furnished
with points, worn to protect the hand, to add force to a blow, and to
disfigure the person struck; as, brass knuckles; – called also knuckle
duster.

To yield; to submit; – used with down, to, or under.

To beat with the knuckles; to pommel.