RIO

n. Rio de Janeiro (Brazil)

officer that operates radar detectors in American Air Force planes (sits in the rear of the plane)

Rio is the Portuguese and Spanish (in which it is spelled río) word for "river". Aside from its use in the name of many rivers (see especially Rio Grande/Río Bravo del Norte), Rio or RIO is used in a number of other ways.
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Noun
1. the former capital and 2nd largest city of Brazil; chief Brazilian port; famous as a tourist attraction
(synonym) Rio de Janeiro
(hypernym) city, metropolis, urban center
(part-holonym) Brazil, Federative Republic of Brazil, Brasil
(member-meronym) Carioca

n. Rio, part of several place names (such as Rio de Janeiro)

n. Rio, Rio de Janeiro (Brazil)

n. Rio, part of several place names (such as Rio de Janeiro)