<Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (August 2011) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (August 2011) (Learn how and when to remove this template message) </Td> </Tr> <P> A tributary or affluent is a stream or river that flows into a larger stream or main stem (or parent) river or a lake . A tributary does not flow directly into a sea or ocean . Tributaries and the main stem river drain the surrounding drainage basin of its surface water and groundwater, leading the water out into an ocean . </P> <P> A confluence, where two or more bodies of water meet together, usually refers to the joining of tributaries . </P>

A small river or stream flowing into a large river