/ Dictionary / Index K knuck: Meaning and Definition of Find definitions for: knuck Pronunciation: (nuk), [key] — n. knuckle. a pair of brass knuckles. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. knubby knuckle Related Content Daily Word Quiz: penurious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language