n. & v.
n. 1 the bone at a finger-joint, esp. that adjoining the hand. 2 a a projection of the carpal or tarsal joint of a quadruped. b a joint of meat consisting of this with the adjoining parts, esp. of bacon or pork.
v.tr. strike, press, or rub with the knuckles. go the knuckle Austral. sl. fight, punch. knuckle-bone 1 bone forming a knuckle. 2 the bone of a sheep or other animal corresponding to or resembling a knuckle. 3 a knuckle of meat. knuckle-bones 1 animal knuckle-bones used in the game of jacks. 2 the game of jacks. knuckle down (often foll. by to) 1 apply oneself seriously (to a task etc.). 2 (also knuckle under) give in; submit. knuckle sandwich sl. a punch in the mouth. rap on (or over) the knuckles see RAP(1). knuckly adj.
[ ME knokel f. MLG, MDu. knökel, dimin. of knoke bone ]