Definition
Aircraft systems designed to prevent ice from forming on protected surfaces or components by heating them, applying a fluid, or otherwise treating them before ice can accumulate. Anti-icing systems are activated before entering icing conditions and operate continuously to keep ice from bonding to the surface in the first place.
Plain English
Equipment that stops ice from forming on the aircraft, used as a preventive measure before flying into icing conditions rather than after ice has already built up.
Context Anchor
Seen in discussions of induction icing, carburetor heat, alternate air, and cold-weather or visible-moisture operation.
Derivation
Anti- comes from Greek meaning against or before. So anti-icing literally means acting against icing before it happens — which captures the key idea: it's preventive, not corrective.
Why Pilots Care
Prevents engine power loss or flameout caused by ice blocking airflow into the induction system.
Grounding Statement
If ice could form where air needs to flow, an anti-icing system is there to help keep that path open.
Intuition Check
Anti-icing does not simply mean “anything related to ice.” It usually means preventing ice from forming, not waiting until a large buildup has already happened.
Example Sentence 1
Before climbing into the cloud layer with reported icing, the pilot turned on the pitot heat and other anti-icing systems.
Example Sentence 2
Induction anti-icing kept the carburetor throat clear of ice during the descent through freezing rain.