/ Dictionary / Index A Arecibo Observatory: Meaning and Definition of Find definitions for: Areci'bo Observ'atory Pronunciation: [key] a radio-astronomy and ionospheric observatory near Arecibo, Puerto Rico: site of one of the world's largest single-dish radio telescopes, 1000 ft. (305 m) in diameter. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Arecibo arecoline Related Content Daily Word Quiz: simian Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language