sky marshal

American  

noun

1. an armed plainclothes federal marshal riding on an airliner to protect against skyjacking.

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sky marshal British  

noun

1. an armed security guard on a commercial aircraft

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Etymology

Origin of sky marshal

An Americanism dating back to 1965–70

Example Sentences

He helped develop the sky marshal program to counteract hijackers.

From New York Times

He also helped develop the federal sky marshal program, his family said.

From Washington Post