/ Dictionary / Index N nephelinite: Meaning and Definition of Find definitions for: neph•e•lin•ite Pronunciation: (nef'u-lu-nīt"), [key] — n. Petrog. a fine-grained, dark rock of volcanic origin, essentially a basalt containing nepheline but no feldspar and little or no olivine. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: nephelinite (Thesaurus) nepheline nephelometer Related Content Daily Word Quiz: vertigo Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language