Plain English Meaning
A heated patch on the windshield that melts ice and clears fog from a small viewing area, similar in idea to the heated rear window of a car.
Full Definition
A small panel of laminated glass or plastic, embedded with electrical heating elements, fitted to a section of the windshield to keep that area clear of ice, frost, and fog by warming the surface to a temperature above the freezing point.
Context Anchor
Seen in discussions of windshield ice protection, especially on aircraft that need a heated viewing area during flight in icing conditions.
Why Pilots Care
Maintains clear forward visibility essential for safe flight and in icing conditions.