Mouth
The streams that contribute to a river system are called tributaries.
waters of the ocean that move in giant streams are called currents.
They are called naiads.
jet streams
creeks
When two streams join together, it is called confluence. This natural phenomenon occurs where two rivers or streams meet and merge into a larger body of water.
It is usually the other way round. Moving in the direction of water flow, streams merge together to form larger rivers, the streams are called the river's tributaries. The point of joining is called a "confluence".
a glacial deposit that is sorted and layered by streams or melted water is called
When two streams come together, it is called a confluence. At a confluence, the two streams merge to form a single stream.
tributaries
These are often called currents, but sometimes are just called streams e.g. The Gulf Stream
Streams of molten lava out of a volcano are called 'lava flows'.