- Drainage basin - the area of land drained by a river.
- Catchment area - the area within the drainage basin.
- Watershed - the edge of highland surrounding a drainage basin. Marks boundary between two drainage basins.
- Source - The start of a river.
- Confluence - the point at which two rivers or streams join.
- Tributary - a stream or smaller river which joins a larger stream or river.
- Mouth - the point where the river comes to the end, usually when entering a sea.
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- Hydraulic action - the force of the river against the banks can cause air to be trapped in cracks and crevices. The pressure weakens the banks and gradually wears it away.
- Abrasion - rocks carried along by the river wear down the river bed and banks.
- Attrition - rocks being carried by the river smash together and break into smaller, smoother and rounder particles.
- Solution - soluble particles are dissolved into the river.
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