|any of several long-snouted usually freshwater dolphins of South America and southern Asia|
any of four or five species of small, usually freshwater aquatic mammals that are related to whales (order Cetacea). These dolphins are found in rivers of south-central Asia, China, and South America and in the coastal waters of Brazil, Argentina, and Uruguay. River dolphins have long beaks and rounded foreheads, distinguishing them from more familiar-looking dolphins such as the bottle-nosed dolphin of the family Delphinidae.
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