Tributaries
The streams that contribute to a river system are called tributaries.
It is called a river
tributaries
A stream or brook can get bigger and become a river.
Streams are merely tributaries of rivers. A river is the wider channel into which smaller creeks, streams and rivers flow. (Streams do not flow out of rivers.) Streams carry water from higher sources, emptying into the river. As more streams empty into a river, it tends to become broader, simply because of the greater volume of water it is carrying.
The streams that contribute to a river system are called tributaries.
Tributaries
All rivers are streams but not all streams are rivers. There is a defined method (Link) of sizing flowing water, all these features are streams and are ranked as 1st through 12th order streams. The systems starts with what would be called in non-scientific terms brooks and works up to rivers. Going up in size and strength, streams that are classified as 4th through 6th order are medium streams while anything larger is a river. Examples:The Ohio River in the United States is an 8th order streamThe Mississippi River is a 10th order stream.The Amazon in South America, is a 12th order stream.
They are called tributaries.
Rivers and streams that flow in to a larger river are called tributaries. They all form in the same spot.
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Streams run into larger rivers.