deactivatePronunciation: /diːˈaktɪveɪt/Definition of deactivate verb [with object] make (something) inactive by disconnecting or destroying it:the switch deactivates the alarm Military remove from active duty. Derivatives deactivationPronunciation: /-ˈveɪʃ(ə)n/ noun deactivator noun deactivate in other Oxford dictionaries Definition of deactivate in the US English dictionary