The term 'Locked Down' can be described by two crossword solutions: 'Battened' and 'Secured'. Battened is an 8-letter word which means to fasten or secure something with strips of wood or metal. Secured is a 7-letter word which means to make something safe or protected. Both words refer to the act of making something secure, usually by locking it down. This phrase is often used in reference to security measures, such as when a building is locked down during an emergency.