activate

verb

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

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
activation noun
activator 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.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Keep your headlights on and activate emergency flashers to alert other drivers of your position. Southern California Weather Report, Orange County Register, 13 Mar. 2025 Carsley said during his spell as interim coach that White still had his ‘do not disturb’ status activated after Southgate’s departure last summer. Oliver Kay, The Athletic, 13 Mar. 2025 The system can only be activated under certain driving conditions, requiring specific environmental and traffic criteria to be met. Kurt Knutsson, Cyberguy Report, Fox News, 13 Mar. 2025 The discovery came after an alarm on a TSA body scanner was activated in the man’s groin area. Gabrielle Rockson, People.com, 12 Mar. 2025 See All Example Sentences for activate

Word History

Etymology

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

First Known Use

1624, in the meaning defined at transitive sense

Time Traveler
The first known use of activate was in 1624

Browse Nearby Words

Cite this Entry

“Activate.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/activate. Accessed 16 Mar. 2025.

Kids Definition

activate

verb
ac·​ti·​vate ˈak-tə-ˌvāt How to pronounce activate (audio)
activated; activating
1
: to make active
2
: to make (as molecules) more chemically active
3
: to make (a substance) give off radioactive particles, give off light at low temperatures, be easily affected by light, or carry an electric charge under the influence of light or other electromagnetic radiation
4
: to treat (as carbon or alumina) so as to improve the amount of adsorption
5
: to place on active military duty
activate the reserves
activation noun
activator noun

Medical Definition

activate

transitive verb
ac·​ti·​vate ˈak-tə-ˌvāt How to pronounce activate (audio)
activated; activating
: 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
activation noun

More from Merriam-Webster on activate

Last Updated: - Updated example sentences
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