Plain English Meaning

A control in the cockpit that sends warm air into the carburetor to melt ice that can form there and choke the engine.

Full Definition

A system that routes air through a heated shroud around the engine exhaust before it enters the carburetor, raising the temperature of the induction air to melt or prevent ice forming inside the carburetor.

Context Anchor

You encounter carburetor heat during the before-takeoff engine check, and in flight when conditions could allow ice to form in the carburetor.

Derivation

From 'carburetor' (the device that mixes and air for the engine, from French carburer, to combine with ) plus '.' The name simply describes what the system does: it heats the air going into the carburetor.