/ Dictionary / Index F Fraunhofer lines: Meaning and Definition of Find definitions for: Fraun'hofer lines" Pronunciation: [key] — Astron. Astron. the dark lines of the solar spectrum. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Fraunhofer Fravashi Related Content Daily Word Quiz: feline Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language