erosion

n. gradual wearing away of the Earth by wind or water; disintegration; deterioration

Erosion is displacement of solids (soil, mud, rock and other particles) usually by the agents of currents such as, wind, water, or ice by downward or down-slope movement in response to gravity or by living organisms (in the case of bioerosion).Erosion is distinguished from weathering, which is the breaking down of rock and particles through processes where no movement is involved, although the two processes may be concurrent.Erosion is an intrinsic natural process but in many places it is increased by human land use. Poor land use practices include deforestation, overgrazing, unmanaged construction activity and road or trail building. However, improved land use practices can limit erosion, using techniques like terrace-building and tree planting.
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Erosion /ero·sion/ an eating or gnawing away; a shallow or superficial ulceration; in dentistry, the wasting away or loss of substance of a tooth by [more]Erosion - Community and Resources

Noun
1. (geology) the mechanical process of wearing or grinding something down (as by particles washing over it)
(synonym) eroding, eating away, wearing, wearing away
(hypernym) geological process, geologic process
(hyponym) chatter mark
(derivation) erode, eat away, fret
(classification) geology
2. condition in which the earth's surface is worn away by the action of water and wind
(hypernym) environmental condition
(derivation) erode, gnaw, gnaw at, eat at, wear away
3. a gradual decline of something; "after the accounting scandal there was an erosion of confidence in the auditors"
(hypernym) decline, diminution
4. erosion by chemical action
(synonym) corrosion, corroding
(hypernym) chemical process, chemical change, chemical action
(hyponym) pitting, roughness, indentation

n. erosion, gradual wearing away of the Earth by wind or water; disintegration, deterioration