The
Paraná River (, ) is a river in south Central South America, running through
Brazil,
Paraguay, and
Argentina for some . It is second in length only to the
Amazon River among South American rivers. The name Paraná is an abbreviation of the phrase "para rehe onáva", which comes from the
Tupi language and means "like the sea" (that is, "as big as the sea"). It merges first with the
Paraguay River and then farther downstream with the
Uruguay River to form the
Río de la Plata and empties into the Atlantic Ocean.