/ Dictionary / Index G Great Rift: Meaning and Definition of Find definitions for: Great' Rift' Pronunciation: [key] — Astron. Astron. a group of large dark clouds in the Milky Way between the constellations Cygnus and Sagittarius. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. great rhododendron Great Rift Valley Related Content Daily Word Quiz: languid Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language