A stream smaller than a river is known as a creek
A stream or river called that flows into a larger stream or river is called a tributary.
tributary
The smaller stream is the tributary of the larger river.
The smaller stream is a tributary of a larger stream, river or lake.
Tributary.
It is called a tributary.
Answer!-Usually the start of a river is called its source and the end of the river is called the mouth.
The smaller river is a tributary to the big one.
tributary is the collective term A tributary is a smaller stream which flows into a larger river. The name of an individual stream depends on the size of the stream. It may be a river or a creek or a canal if it is manmade.
Tributary
A small freshwater river or stream flowing into a larger river is called a tributary or feeder river. A tributary is a stream or river that flows into a mainstem (or parent) river or a lake. For example, a tributary can be a creek that flows into a river. Or it can be a small river that flows into a larger river. A tributary does not flow directly into a sea or ocean. Some large rivers can have up to 100 tributaries. The spot where the smaller and larger river meet is called a "confluence". In contrast, a body of water that branches off and flows away from the main river is called a distributary.
A tributary