no-fly zone
From Longman Dictionary of Contemporary EnglishRelated topics: Airforce, Airno-fly zoneno-ˈfly ˌzone noun [countable] PMPTTAan area that only particular aircraft are allowed to enter, and in which other aircraft could be attackedExamples from the Corpusno-fly zone• In the south the enforcement of a no-fly zone by western aircraft has raised the possibility of a Shia secession.• S.-enforced no-fly zone.• However, those ships can not enforce the no-fly zone.