- (transitive) to make (a bomb, etc) harmless or inoperative
- (intransitive) to become less radioactive
WordReference Random House Learner's Dictionary of American English © 2026
de•ac•ti•vate /diˈæktəˌveɪt/USA pronunciation
v. [ ~ + obj], -vat•ed, -vat•ing.
WordReference Random House Unabridged Dictionary of American English © 2026- to make inactive:to deactivate a chemical.
- Militaryto disband or break up (a military unit).
de•ac•ti•vate
(dē ak′tə vāt′),USA pronunciation v., -vat•ed, -vat•ing.
v.t.
v.i.
de•ac′ti•va′tion, n.
de•ac′ti•va′tor, n.
v.t.
- to cause to be inactive;
remove the effectiveness of. - Militaryto demobilize or disband (a military unit).
- Militaryto render (a bomb, shell, or the like) inoperative, esp. by disconnecting, removing, or otherwise interfering with the action of the fuze.
- Chemistryto render (a chemical, enzyme, catalyst, etc.) inactive.
v.i.
- Chemistry[Physical Chem.]to lose radioactivity.
- de- + activate 1900–05
de•ac′ti•va′tor, n.
Collins Concise English Dictionary © HarperCollins Publishers::
deactivate /diːˈæktɪˌveɪt/ vb
'deactivate' also found in these entries (note: many are not synonyms or translations):