When it comes to CORROSION, you just have to look at the underlying Latin term to get an idea of what you're dealing with here: “corrodere” means “gnawing away” or even “eating away.” Sounds bad doesn't it!? Is it also: CORROSION refers to the destruction of a substance through a chemical or electrochemical reaction with its environment. For example, free carbonic acid can damage pipes, but the oxidation of a metal (and thus the formation of rust and patina) is also referred to as CORROSION.