/ Dictionary / Index N nacreous: Meaning and Definition of Find definitions for: na•cre•ous Pronunciation: (nā'krē-us), [key] — adj. of or pertaining to nacre. resembling nacre; lustrous; pearly. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: nacreous (Thesaurus) nacred nacreous cloud Related Content Daily Word Quiz: modify Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language