/ Dictionary / Index K knuckle sandwich: Meaning and Definition of Find definitions for: knuck'le sand'wich Pronunciation: [key] — Slang. Slang. a punch in the mouth with a clenched fist. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. knuckle joint Knudsen Related Content Daily Word Quiz: morose Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language