The definition of “Green” as it pertains to “Green Chemicals” or “Green Corrosion Inhibition” seems to be vague. Even though the scientific and engineering communities use this word frequently, there seems to be a lack of consensus on the definition. The paper describes the various definitions and their overall impact on “Green”. Key Words: green, inhibitor, chemical, emissions, renewable, biodegradable, non-toxic, low toxicity, benign, biochemical