corrosion

n. wear, deterioration; rust, oxidation

Corrosion is breaking down of essential properties in a material due to reactions with its surroundings. In the most common use of the word, this means a loss of an electron of metals reacting with water and oxygen. Weakening of iron due to oxidation of the iron atoms is a well-known example of electrochemical corrosion. This is commonly known as rust. This type of damage usually affects metallic materials, and typically produces oxide(s) and/or salt(s) of the original metal. Corrosion also includes the dissolution of ceramic materials and can refer to discoloration and weakening of polymers by the sun's ultraviolet light.
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Corrosion, n an electrolytic or chemical attack of a surface. Usually refers to the attack of a metal surface. [more]Corrosion - Community and Resources

Noun
1. a state of deterioration in metals caused by oxidation or chemical action
(hypernym) deterioration, impairment
(derivation) corrode, rust
2. erosion by chemical action
(synonym) corroding, erosion
(hypernym) chemical process, chemical change, chemical action
(hyponym) pitting, roughness, indentation
(derivation) corrode, eat, rust

n. corrosion, erosion; corrosive