/ Dictionary / Index R Royal Greenwich Observatory: Meaning and Definition of Find definitions for: Roy'al Green'wich Observ'atory Pronunciation: [key] the national astronomical observatory of Great Britain, housed in a castle in E Sussex; formerly located at Greenwich. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. royal flush Royal Highness Related Content Daily Word Quiz: crutiny Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language