/ Dictionary / Index G galactic plane: Meaning and Definition of Find definitions for: galac'tic plane' Pronunciation: [key] — Astron. Astron. the plane of the galactic equator. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. galactic nebula galactic pole 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