/ Dictionary / Index G galactic nebula: Meaning and Definition of Find definitions for: galac'tic neb'ula Pronunciation: [key] — Astron. Astron. a nebula in the Milky Way. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. galactic longitude galactic plane Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language