- The joint of a finger, particularly when made prominent by
the closing of the fingers. - 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.
2 . Knuckle
[ v. i.]
- To yield; to submit; -- used with down, to, or under.