Knuc·kle n.
 1. The joint of a finger, particularly when made prominent by the closing of the fingers.
 2. The kneejoint, or middle joint, of either leg of a quadruped, especially of a calf; -- formerly used of the kneejoint of a human being.
    With weary knuckles on thy brim she kneeled sadly down.   --Golding.
 3. The joint of a plant. [Obs.]
 4. Mech. The joining parts of a hinge through which the pin or rivet passes; a knuckle joint.
 5. 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.
 6. 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.]
 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.
 Pin, n.
 1. A piece of wood, metal, etc., generally cylindrical, used for fastening separate articles together, or as a support by which one article may be suspended from another; a peg; a bolt.
 With pins of adamant
 And chains they made all fast.   --Milton.
 2. Especially, a small, pointed and headed piece of brass or other wire (commonly tinned), largely used for fastening clothes, attaching papers, etc.
 3. Hence, a thing of small value; a trifle.
    He . . . did not care a pin for her.   --Spectator.
 4. That which resembles a pin in its form or use; as: (a) A peg in musical instruments, for increasing or relaxing the tension of the strings. (b) A linchpin. (c) A rolling-pin. (d) A clothespin. (e) Mach. A short shaft, sometimes forming a bolt, a part of which serves as a journal. See Illust. of Knuckle joint, under Knuckle. (f) Joinery The tenon of a dovetail joint.
 5. One of a row of pegs in the side of an ancient drinking cup to mark how much each man should drink.
 6. The bull's eye, or center, of a target; hence, the center. [Obs.] “The very pin of his heart cleft.”
 7. Mood; humor. [Obs.] “In merry pin.”
 8. Med. Caligo. See Caligo.
 9. An ornament, as a brooch or badge, fastened to the clothing by a pin; as, a Masonic pin.
 10. The leg; as, to knock one off his pins. [Slang]
 Banking pin Horol., a pin against which a lever strikes, to limit its motion.
 Pin drill Mech., a drill with a central pin or projection to enter a hole, for enlarging the hole, or for sinking a recess for the head of a bolt, etc.; a counterbore.
 Pin grass. Bot. See Alfilaria.
 Pin hole, a small hole made by a pin; hence, any very small aperture or perforation.
 Pin lock, a lock having a cylindrical bolt; a lock in which pins, arranged by the key, are used instead of tumblers.
 Pin money, an allowance of money, as that made by a husband to his wife, for private and personal expenditure.
 Pin rail Naut., a rail, usually within the bulwarks, to hold belaying pins. Sometimes applied to the fife rail. Called also pin rack.
 Pin wheel. (a) A contrate wheel in which the cogs are cylindrical pins. (b) Fireworks A small coil which revolves on a common pin and makes a wheel of yellow or colored fire.
 Spade, n.
 1. An implement for digging or cutting the ground, consisting usually of an oblong and nearly rectangular blade of iron, with a handle like that of a shovel. “With spade and pickax armed.”
 2.  One of that suit of cards each of which bears one or more figures resembling a spade.
    =\“Let spades be trumps!” she said.\=   --Pope.
 3. A cutting instrument used in flensing a whale.
 Spade bayonet, a bayonet with a broad blade which may be used digging; -- called also trowel bayonet.
 Spade handle Mach., the forked end of a connecting rod in which a pin is held at both ends. See Illust. of Knuckle joint, under Knuckle.
 knuckle joint
      n 1: a joint of a finger when the fist is closed [syn: knuckle,
            metacarpophalangeal joint]
      2: a joint allowing movement in one plane only [syn: hinge
         joint]