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Inflections of 'knuckle ' (v ): (⇒ conjugate )knuckles v 3rd person singular knuckling v pres p knuckled v past knuckled v past p
WordReference Random House Learner's Dictionary of American English © 2026 knuck•le /ˈnʌkəl/USA pronunciation
n., v., -led, -ling. n.
Anatomy [ countable ] any joint of a finger, esp. where a finger bends, or where a finger meets the hand.
v.
knuckle down , [ no object]
to apply oneself with energy; to work earnestly; become serious.
Also, knuckle under. [ no object] to admit that one is defeated; to submit; yield:He won't ever knuckle under to your threats.
WordReference Random House Unabridged Dictionary of American English © 2026 knuck•le
(nuk′ əl),USA pronunciation n., v., -led, -ling. n.
Anatomy a joint of a finger, esp. one of the articulations of a metacarpal with a phalanx.
Anatomy the rounded prominence of such a joint when the finger is bent.
Food a joint of meat, consisting of the parts about the carpal or tarsal joint of a quadruped.
Building an angle or protrusion at the intersection of two members or surfaces, as in the timbers of a ship or in a roof.
See brass knuckles.
Building a cylindrical projecting part on a hinge, through which an axis or pin passes; the joint of a hinge.
Building (in a wire mesh) a bend in a wire crossing another wire.
Furniture (on a chair arm) one of the ridges left at the front end by longitudinal flutes carved to accommodate the fingers.
Nautical, Naval Terms a pronounced edge formed by a change in the form of the shell of a hull.
v.t.
to rub or press with the knuckles.
Games [ Marbles.] to shoot (a marble) from the thumb and forefinger.
knuckle down :
to apply oneself vigorously and earnestly; become serious:Just knuckle down for an hour or so and finish the work.
Also, knuckle under. to submit; yield.
1325–75; Middle English knokel (akin to Dutch kneukel, German Knöchel ), diminutive of a word represented by Dutch knok, German Knochen bone; see -le
knuck′ ly , adj.
Collins Concise English Dictionary © HarperCollins Publishers::
knuckle /ˈnʌkə l / n a joint of a finger, esp that connecting a finger to the hand a joint of veal, pork, etc, consisting of the part of the leg below the knee joint, often used in making stews or stock near the knuckle ⇒ informal approaching indecency vb (transitive ) to rub or press with the knuckles (intransitive ) to keep the knuckles on the ground while shooting a marble Etymology: 14th Century: related to Middle High German knöchel, Middle Low German knoke bone, Dutch knok ˈknuckly adj
'knuckle ' also found in these entries (note: many are not synonyms or translations):