ac·​ti·​vate | \ ˈak-tə-ˌvāt How to pronounce activate (audio) \
activated; activating

Definition of activate

transitive verb

: to make active or more active: such as
a(1) : to make (something, such as a molecule) reactive or more reactive
(2) : to convert (something, such as a provitamin) into a biologically active derivative
b : to make (a substance) radioactive
c : to treat (a substance, such as carbon or alumina) so as to improve adsorptive properties
d(1) : to set up or formally institute (an organized group, such as a military unit) with the necessary personnel and equipment
(2) : to put (an individual or unit) on active duty

intransitive verb

: to become active

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Other Words from activate

activation \ ˌak-​tə-​ˈvā-​shən How to pronounce activation (audio) \ noun
activator \ ˈak-​tə-​ˌvā-​tər How to pronounce activator (audio) \ noun

Examples of activate in a Sentence

Touch the screen to activate the system. activate and then deactivate a mechanism The camera is activated by pushing a button. The bomb was activated by remote control. Sunlight activates a chemical reaction in the plant's leaves. vitamins that activate the growth of new cells The President has activated the reserves.
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Recent Examples on the Web Wilder Penfield, a neurosurgeon active in the middle of the 20th century, often used an electrical current to activate different areas on the surface of his patients’ brains. Grace Huckins, Wired, "Scientists Taught Mice to Smell an Odor That Doesn’t Exist," 25 June 2020 As Arizona hospitals were urged to activate emergency plans, Florida on Saturday saw its largest single-day count of cases since the pandemic began. Chronicle Staff,, "Coronavirus news from the Bay Area: June 14-15," 16 June 2020 The past few weeks have seen wider spread in inland states, including Arkansas, Texas and Arizona, which has told its hospitals to activate emergency plans. Emma Reynolds, CNN, "Confusion reigns as countries loosen coronavirus lockdowns and cases rise," 13 June 2020 Councilman Tom Troyer asked under what conditions officers will activate the body cams. Beth Mlady, cleveland, "Brook Park Police Department will get body cameras," 12 June 2020 After the meeting, Esper and other military leaders began a full-court press effort to encourage the nation’s governors to activate their National Guard forces on state duty. NBC News, "Joint Chiefs Chairman Milley discussed resigning over role in Trump's church photo op," 11 June 2020 But to stay the president’s hand, the Pentagon needed to activate a lot more guard troops quickly, and states were reluctant to put any troops, guard or otherwise, on the street of their cities. Jamie Mcintyre, Washington Examiner, "The Pentagon defused Trump's threat to invoke the Insurrection Act," 11 June 2020 Christ also told hospitals to fully activate their emergency plan, in keeping with an executive order from Gov. Doug Ducey that called for expanding hospital bed capacity, first by 25% and then by 50%. USA TODAY, "Infected ferry, Crater Lake, mask-shaming, virtual farmers market: News from around our 50 states," 10 June 2020 Michael Pryor, head of Trello at parent company Atlassian Corp., said designers placed the toggle to activate colorblind mode in Trello’s main interface, rather than burying it deep within a settings menu. Katie Deighton, WSJ, "Colorblind Users Push Technology Designers to Use Signals Beyond Color," 5 June 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'activate.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of activate

1624, in the meaning defined at transitive sense

History and Etymology for activate

active entry 1 + -ate entry 4, probably as adaptation of French activer, going back to Middle French, derivative of actif active entry 1

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Time Traveler for activate

Time Traveler

The first known use of activate was in 1624

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Statistics for activate

Last Updated

30 Jun 2020

Cite this Entry

“Activate.” Dictionary, Merriam-Webster, Accessed 8 Jul. 2020.

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More Definitions for activate


How to pronounce activate (audio)

English Language Learners Definition of activate

: to cause (a device) to start working
chemistry : to cause (a chemical reaction or natural process) to begin
chiefly US : to order (soldiers) to serve in a war


ac·​ti·​vate | \ ˈak-tə-ˌvāt How to pronounce activate (audio) \
activated; activating

Kids Definition of activate

: to start working or cause to start working Activate the alarm.
ac·​ti·​vate | \ ˈak-tə-ˌvāt How to pronounce activate (audio) \
activated; activating

Medical Definition of activate

: to make active or more active: as
a : to convert into a biologically active derivative or form activated plasminogen
b : to make biologically or molecularly active activate protein synthesis The [spinal] cord also contains neuronal circuits …that can be activated by incoming sensory signals without input from the brain …— John W. McDonald et al., Scientific American, September 1999
c : to make (a substance) radioactive

Other Words from activate

activation \ ˌak-​tə-​ˈvā-​shən How to pronounce activation (audio) \ noun

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