[ dee-ak-tuh-veyt ]
See synonyms for deactivate on
verb (used with object),de·ac·ti·vat·ed, de·ac·ti·vat·ing.
  1. to cause to be inactive; remove the effectiveness of.

  2. to demobilize or disband (a military unit).

  1. to render (a bomb, shell, or the like) inoperative, especially by disconnecting, removing, or otherwise interfering with the action of the fuze.

  2. Chemistry. to render (a chemical, enzyme, catalyst, etc.) inactive.

verb (used without object),de·ac·ti·vat·ed, de·ac·ti·vat·ing.
  1. Physical Chemistry. to lose radioactivity.

Origin of deactivate

First recorded in 1900–05; de- + activate

Other words from deactivate

  • de·ac·ti·va·tion, noun
  • de·ac·ti·va·tor, noun

Words Nearby deactivate Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use deactivate in a sentence

  • This ship is crowded with a complete set of automatic defenses that I cant deactivate.

    Garth and the Visitor | L. J. Stecher
  • It will not be possible to deactivate it before 12.45 hours.

    The Lost Kafoozalum | Pauline Ashwell
  • Conn used the manual control to set it down and deactivate it, then got out and went to examine it.

    The Cosmic Computer | Henry Beam Piper

British Dictionary definitions for deactivate


/ (diːˈæktɪˌveɪt) /

  1. (tr) to make (a bomb, etc) harmless or inoperative

  2. (intr) to become less radioactive

  1. (tr) US to end the active status of (a military unit)

  2. chem to return or cause to return from an activated state to a normal or ground state

Derived forms of deactivate

  • deactivation, noun
  • deactivator, noun

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012