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

Other Words from activate

activation \ ˌak-​tə-​ˈvā-​shən How to pronounce activate (audio) \ noun
activator \ ˈak-​tə-​ˌvā-​tər How to pronounce activate (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. See More
Recent Examples on the Web These cyclic dinucleotides are the second messengers that activate STING. William A. Haseltine, Forbes, 26 Apr. 2022 Additionally, the Moderna vaccine spurred relatively higher levels of antibodies that activate immune cells called natural killer cells. Beth Mole, Ars Technica, 31 Mar. 2022 Other back-strengthening exercises rely on stabilization or resisting motion, such as the ones that activate your erector spinae, or your deep lower back muscles. SELF, 25 Mar. 2022 The steering-wheel controls require a deliberate tap to activate, and the sliders for volume and track/channel skip aren't as overly sensitive as other brands. Mark Takahashi, Car and Driver, 3 June 2022 Click on any of the links on this page to automatically activate our FanDuel promo code and this new users offer. Xl Media, cleveland, 2 June 2022 Acting on an order from Newsom, the State Water Resources Control Board voted to adopt emergency drought regulations that require water suppliers to activate their local drought plans to prepare for a shortage of up to 20%. Ian Jamesstaff Writer, Los Angeles Times, 25 May 2022 The emergency decree would allow the government to activate the coal facilities without approval from parliament for up to six months. Time, 24 May 2022 Swing your legs to activate your hamstring for your sprint and backwards running. Perri O. Blumberg, Men's Health, 23 May 2022 See More

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.

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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Dictionary Entries Near activate



activated alumina

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Statistics for activate

Last Updated

19 Jun 2022

Cite this Entry

“Activate.” Dictionary, Merriam-Webster, Accessed 27 Jun. 2022.

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More Definitions for activate


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.


transitive verb
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
c : to make (a substance) radioactive

Other Words from activate

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

More from Merriam-Webster on activate

Nglish: Translation of activate for Spanish Speakers

Britannica English: Translation of activate for Arabic Speakers


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