/ Dictionary / Index N nighty-night: Meaning and Definition of Find definitions for: night•y-night Pronunciation: (nī'tē-nīt'), [key] — interj. Informal. See Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. nighty nigiri-zushi Related Content Daily Word Quiz: dissonant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language