/ Dictionary / Index U Uruguay: Meaning and Definition of Find definitions for: U•ru•guay Pronunciation: (yoor'u-gwā", -gwī" Sp. &oomacr"r&oomacr-gwī'), [key] — n. a republic in SE South America. 2,763,964; 72,172 sq. mi. (186,925 sq. km). Cap.: Montevideo. a river in SE South America, flowing from S Brazil along the boundary of E Argentina into the Río de la Plata. 981 mi. (1580 km) long. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: uruguay (Thesaurus) Uruguaiana Uruk Related Content Daily Word Quiz: acquiesce Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language