Scientific definition of corrosive

The Word 'corrosion' is derived from the Latin verb corrode which means 'to gnaw' indicating how these substances seem to 'gnaw' their way through the flesh. Sometimes the Word 'caustic' is used as a synonym, but by convention 'caustic' generally refers only to strong bases, particularly alkalis, and not to acids, oxidizers, or other non-alkaline corrosives. The term 'acid' is often used imprecisely for all corrosives.

A low concentration of a corrosive substance is usually an irritant. Corrosion of non-living surfaces such as metals is a distinct process. For example, a water/air electrochemical cell corrodes iron to rust. In the Globally Harmonized System, both rapid corrosion of metals and chemical corrosion of skin qualify for the "corrosive" symbol.