/ Dictionary / Index N noctilucent: Meaning and Definition of Find definitions for: noc•ti•lu•cent Pronunciation: (nok"tu-l'sunt), [key] — adj. Meteorol. (of high-altitude clouds) visible during the short night of the summer. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: noctilucent (Thesaurus) noctiluca noctis Related Content Daily Word Quiz: eureka Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language