Plain English Meaning
A cockpit windshield that warms itself so ice and frost cannot stick to it and the pilot can keep seeing out clearly.
Full Definition
An aircraft windscreen built with an internal electrical heating element or heated airflow system that warms the glass to prevent ice, frost, or fog from forming on it during flight.
Context Anchor
Seen in windscreen anti-ice discussions and in aircraft checklists or switch panels for windshield heat.
Why Pilots Care
Ice on the windshield can quickly block forward , making , , and unsafe or impossible.