Definition of "river" []

• A large natural stream of water emptying into an ocean, lake, or other body of water and usually fed along its course by converging tributaries. (noun)
• A stream or abundant flow: a river of tears. (noun)
• Up the river Slang In or into prison. (idiom)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "While this may have been true for the cases of the three earliest civilizations, further study of early Chinese civilization shows that irrigation-based agriculture did not play a major role in developing hierarchical institutions, and the absence of major river valleys in Mesoamerica and the region of the Andes civilization brought an end to the old “river valley theory” of the origins of civilization."
• "_Mississippi_ is a proper noun, because it is the name of an individual river; but _river_ is a common noun, because it is the name of a _species_ of things, and the name _river_ is common to _all_ rivers."
• "I spent most _on the river and in the river_ of the time I stayed there."