Plain English Meaning
Full Definition
The process of removing ice, frost, or snow that has already formed on an aircraft's surfaces, typically using heated fluids, mechanical means such as pneumatic boots that inflate to break ice off the leading edges, or electrically heated elements.
Context Anchor
Seen in discussions of winter operations and aircraft ice-removal equipment, such as inflatable wing devices, heated propellers, or ground deicing before takeoff.
Derivation
From the prefix 'de-' meaning 'remove' and 'icing' meaning 'the buildup of ice.' So 'deicing' literally means removing ice that has already formed.