Río de la Plata

UK: /ˈriːəʊ də lɑː ˈplɑːtə/ US: (Sp. rē′ô ᵺe lä plä′tä)

WordReference Random House Unabridged Dictionary of American English © 2025

Rí•o de la Pla•ta  (Sp. rē′ô ᵺe lä plä′tä). 

1. Place Names See Plata, Río de la. 

Collins Concise English Dictionary © HarperCollins Publishers::

Río de la Plata / ˈriːəʊ də lɑː ˈplɑːtə/ noun

1. See Plata

WordReference Random House Unabridged Dictionary of American English © 2025

Pla•ta  (plä′tä), n. 

Rí•o de la  (rē′ô ᵺe lä), an estuary on the SE coast of South America between Argentina and Uruguay, formed by the Uruguay and Paraná rivers, ab. 185 mi. (290 km) long.Also, La Plata. Also called Pla′ta Riv′er;
 [Brit.] River Plate. 

Collins Concise English Dictionary © HarperCollins Publishers::

Plata / ˈplata/ noun

1. Río de la Plata / ˈrio de la/ ⇒ an estuary on the SE coast of South America, between Argentina and Uruguay, formed by the Uruguay and Paraná Rivers. Length: 275 km (171 miles). Width: (at its mouth) 225 km (140 miles)
   Also known as: La Plata
   English name: River Plate