/ Dictionary / Index N nocturnal: Meaning and Definition of Find definitions for: noc•tur•nal Pronunciation: (nok-tûr'nl), [key] — adj. of or pertaining to the night (opposed to diurnal). done, occurring, or coming at night: nocturnal visit. active at night (opposed to diurnal): nocturnal animals. opening by night and closing by day, as certain flowers (opposed to diurnal). —n. an astrolabe for telling time at night or for determining latitude by the position of certain stars in reference to Polaris. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: nocturnal (Thesaurus) nocturn nocturnal arc Related Content Daily Word Quiz: sylvan Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language