A tributary (or confluent/affluent) is a stream or river which flows into a mainstem (or parent) river, and which does not flow directly into a sea. A stream is a body of Water with a current, confined within a bed and stream-banks "Riverine" redirects here For the use of that term in Maritime geography, see there A mainstem is defined as the principal River within a given Drainage basin, in the case where a number of tributaries discharge into a larger Watercourse "Riverine" redirects here For the use of that term in Maritime geography, see there In orography, tributaries are ordered from those nearest to the source of the river to those nearest to the mouth of the river. Orography is the average height of land measured in geopotential meters, over a certain domain A delta is a Landform where the mouth of a River flows into an Ocean, Sea, Estuary, Lake or another river A confluence is where two or more tributaries or rivers flow together. Confluence, in Geography, describes the meeting of two or more Bodies of water.

The descriptive terms right tributary and left tributary always apply from the perspective of looking downstream (in the direction the current is going), similarly to the river banks. A current, in a River or Stream, is the Flow of Water influenced by Gravity as the water moves Downhill to reduce its A stream bed is the channel bottom of a Stream or River or creek the physical confine of the normal water flow

The opposite of a tributary is a distributary; a river branch that flows away from the main stream. A distributary, or a distributary channel, is a Stream that branches off and flows away from a main stream channel A river and all its tributaries drain the watershed of the river. A drainage basin is an extent of Land where Water from Rain or Snow melt drains downhill into a body of water such as a River,

The Strahler Stream Order examines the arrangement of tributaries in a hierarchy of first, second, third and higher orders, with the first order tributary being typically the least in size. Strahler Stream Order is a simple Hydrology Algorithm used to define stream size based on a hierarchy of tributaries. @@@ main@@@ - title Hierarchy@@@ keywords structure; sociology; information@@@ review@@@ - For example, a second order tributary is composed of two or more first order tributaries combining to form the second order stream.

See also

• Distributary