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.
It’s expected to last into Monday, authorizing the state’s emergency services personnel to be activated as necessary. Jason Ma, Fortune, 12 Oct. 2025 Aside from strengthening the body and improving posture, practicing downward dog also activates blood circulation and may improve digestion. Ana Morales, Vogue, 11 Oct. 2025 The acidic apple cider or white vinegar activates the baking soda, generating carbon dioxide bubbles that help the cookies rise and end up lofty and a bit cake-like, rather than flat. Karla Walsh, Better Homes & Gardens, 11 Oct. 2025 There were 300 members of the Illinois National Guard and 200 members of the Texas National Guard activated under Title 10 and in the Chicago area as of Wednesday, the command previously said. Michelle Watson, CNN Money, 11 Oct. 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 14 Oct. 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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