Plain English Meaning
A chemical added to fuel in tiny amounts to stop water in the fuel from turning into ice and to slow corrosion inside the fuel system.
Full Definition
An organic alcohol-based chemical compound added in small quantities to aviation gasoline (avgas) as a fuel system icing inhibitor (FSII) and anti-corrosion agent. It mixes readily with fuel and helps prevent water in the fuel from freezing into ice crystals that could block fuel lines, filters, or carburetor passages.
Context Anchor
Seen in fuel system discussions, especially when studying fuel contamination, cold-weather operation, and approved fuel additives.