erosion
n//əˈɹoʊʒən//erosion
(uncountable) The result of having been worn away or eroded, as by a glacier on rock or the sea on a cliff face.
(uncountable) The changing of a surface by mechanical action, friction, thermal expansion contraction, or impact.
(uncountable, figurative) The gradual loss of something as a result of an ongoing process.
(uncountable) Destruction by abrasive action of fluids.
(math) In morphology, a basic operation (denoted ⊖); see Erosion (morphology).