deadbolt
From Longman Dictionary of Contemporary EnglishRelated topics: Housedeadboltdead‧bolt /ˈdedbəʊlt $ -boʊlt/ noun [countable] DHHa strong lock often used on doorsExamples from the Corpusdeadbolt• Close the door and mark the area for the deadbolt.• Open the door; hold the striker plate against the door frame in line with the deadbolt mark, and pencil in the outline.