Breadcrumb Home > Dictionary > Index L luminous emittance: Meaning and Definition of Find definitions for: lu'minous emit'tance Pronunciation: [key] — Optics. Optics. luminous flux emitted per unit area. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. luminous luminous energy ✖ Related Content Daily Word Quiz: criticaster Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language