noun
fluvial erosion; river erosion
Technical term in geography and geology for erosion caused by river flow.
河食によって谷が深くなる。
Valleys are deepened by fluvial erosion.
この地形は主に河食で形成された。
This landform was mainly formed by river erosion.
Compound of 河 (river) and 食 (eat/erode), literally 'river eating'. The variant 河蝕 uses 蝕 (erosion/corrosion).