GNU Collaborative International Dictionary of English

Found one definition

1.       
   Knuckle , n. [OE. knokel, knokil, AS. cuncel; akin to D. knokkel, OFries. knokele, knokle, G. knöchel, Sw. knoge, Dan. knokkel, G. knochen bone, and perh. to E. knock.]
   The joint of a finger, particularly when made prominent by the closing of the fingers.
   Davenant.
   
   1913 Webster
   The kneejoint, or middle joint, of either leg of a quadruped, especially of a calf; -- formerly used of the kneejoint of a human being.
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   With weary knuckles on thy brim she kneeled sadly down.
   Golding.
   
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   The joint of a plant. [Obs.]
   Bacon.
   
   1913 Webster
   (Mech.) The joining parts of a hinge through which the pin or rivet passes; a knuckle joint.
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   (Shipbuilding) 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.
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   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; -- called also knuckle duster, knuckles or brass knuckles. [Slang.]
   1913 Webster
   Knuckle joint (Mach.), a hinge joint, in which a projection with an eye, on one piece, enters a jaw between two corresponding projections with eyes, on another piece, and is retained by a pin which passes through the eyes and forms the pivot. -- Knuckle of veal (Cookery), the lower part of a leg of veal, from the line of the body to the knuckle.
   1913 Webster