noun
denudation; degradation
Geological term for the wearing away of the Earth's surface by processes such as weathering and erosion.
削剥作用によって、長い年月をかけて山が削られていく。
Through denudation, mountains are worn down over long periods of time.
浸食 (erosion) specifically refers to the removal of material by water, wind, or ice, while 削剥作用 (denudation) is a broader term that includes erosion and other processes that lower the land surface.
Compound of 削剥 (さくはく, 'denudation, stripping') and 作用 (さよう, 'action, effect'). The exact historical derivation is uncertain; the spelling is conventionally associated with geological denudation.