Erosion

Webster's Dictionary of the English Language

·noun The act or operation of eroding or eating away.

II. Erosion ·noun The state of being eaten away; corrosion; canker.

III. Erosion ·add. ·noun The wearing away of the earth's surface by any natural process. The chief agent of erosion is running water; minor agents are glaciers, the wind, and waves breaking against the coast.