Plain English Meaning
A small gauge in the cockpit that shows how warm or cold the air is inside the carburetor, so the pilot can spot icing risk and check that carb heat is working.
Full Definition
A cockpit instrument that displays the temperature of the air inside the carburetor intake, used by the pilot to detect conditions favorable to carburetor icing and to verify the effect of carburetor heat.
Context Anchor
Seen in airplanes with engines, especially during in cool, damp air or when using carburetor heat.