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- Hydraulic action
- Erosion by the force and pressure of moving water entering cracks in rock, compressing air, and weakening the rock structure
- Abrasion (corrasion)
- Erosion of the bed and banks by the river's own load — particles are dragged across surfaces, wearing them away like sandpaper
- Attrition
- The wearing down of load particles as they collide with each other and with the bed — particles become smaller and rounder downstream
- Corrosion (solution)
- Chemical erosion of soluble rock (especially limestone and chalk) by slightly acidic river water — rock is dissolved and carried away in solution
- Traction
- Transportation of large boulders and cobbles by rolling them along the riverbed
- Saltation
- Transportation of medium-sized pebbles in a bouncing or hopping motion along the riverbed
- Suspension
- Transportation of very fine particles (silt and clay) carried within the body of the flowing water — makes rivers appear brown or cloudy
- Solution
- Transportation of dissolved minerals within the water — invisible, but significant in limestone and chalk catchments
- Discharge
- The volume of water passing a given point in a river per second, measured in cumecs (m³/s) — increases downstream as tributaries add water
- Competence
- The maximum size of particle a river can carry at a given velocity — increases with velocity; when velocity drops, competence drops and deposition occurs
- Capacity
- The total amount (volume) of load a river can carry — increases with discharge
- Meander
- A sinuous (S-shaped) bend in a river formed by unequal erosion on the outside of bends and deposition on the inside
- River cliff
- A steep, near-vertical bank on the outside of a meander bend, formed by lateral erosion undercutting the bank
- Point bar (slip-off slope)
- A gentle slope of deposited sediment on the inside of a meander bend, built up by reduced velocity and helical flow
- Ox-bow lake
- A crescent-shaped lake formed when a highly exaggerated meander is cut off from the main channel, usually during a flood event
- Floodplain
- The flat, wide valley floor flanking the lower course of a river, built up from alluvium deposited by repeated flooding events over thousands of years
- Levée
- A natural embankment of sediment built up alongside the river channel by repeated deposition of coarse material during flood events
- Alluvium
- Fine silt and clay deposited by a river during flooding — builds the floodplain and creates highly fertile agricultural soils
- Interlocking spur
- Projecting ridges of resistant rock in the upper course that the river winds between, creating a zigzag plan view — they interlock like the teeth of a zip
- Plunge pool
- A deep, circular pool at the base of a waterfall formed by the abrasive action of falling water and swirling boulders
- Gorge
- A steep-sided, narrow valley formed in the wake of a retreating waterfall
- Hydraulic radius
- The ratio of cross-sectional area to wetted perimeter — a measure of channel efficiency; higher hydraulic radius = lower friction = faster flow
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