← BackshareGuessnonopening/ˌnɑnˈoʊ.pə.nɪŋ/adjectiveThat does not open; designed to stay closed or not capable of being opened.The package had a nonopening seal that had to be cut.She bought a nonopening locket to keep her photo safe.The museum has a nonopening window for security reasons.SynonymsfixedsealedAntonymsopening