activate

American  

[ak-tuh-vayt] / ˈæk təˌveɪt /

verb (used with object)

• activates,
  present (3rd person singular)
• activated,
  past participle,  past
• activating
  present participle

1. to make active; cause to function or act.

   Synonyms:

   start, actuate

   Antonyms:

   check, halt, stop

2. Physics.

   1. to render more reactive; excite.

      to activate a molecule.

   2. to induce radioactivity.

3. to aerate (sewage) in order to accelerate decomposition of impure organic matter by microorganisms.

4. Chemistry.

   1. to make (carbon, a catalyst, molecules, etc.) more active.

   2. to hasten (reactions) by various means, as heating.

5. to place (a military unit or station) on an active status in an assigned capacity.

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verb (used without object)

• activates,
  present (3rd person singular)
• activated,
  past participle,  past
• activating
  present participle

1. to become active or functional.

activate British  

/ ˈæktɪˌveɪt /

verb

1. to make active or capable of action

2. physics to make radioactive

3. chem

   1. to increase the rate of (a reaction)

   2. to treat (a substance, such as carbon or alumina) so as to increase powers of adsorption

4. physiol to prepare by arousal (the body or one of its organs (e.g. the brain)) for action

5. to purify (sewage) by aeration

6. military to create, mobilize, or organize (a unit)

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Other Word Forms

Derived Forms

• activation
  noun
• activator
  noun
• nonactivation
  noun
• overactivate
  verb (used with object)
• superactivate
  verb (used with object)
• unactivated
  adjective

Inflected Forms

Participles

• activating
  present
• activated
  past

Conjugated Forms

Present

• activate
  simple
• activates
  simple
• have activated
  perfect
• has activated
  perfect
• am activating
  progressive
• are activating
  progressive
• is activating
  progressive
• have been activating
  perfect progressive
• has been activating
  perfect progressive

Past

• activated
  simple
• had activated
  perfect
• was activating
  progressive
• were activating
  progressive
• had been activating
  perfect progressive

Future

• will activate
  simple
• will have activated
  perfect
• will be activating
  progressive
• will have been activating
  perfect progressive

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Etymology

Origin of activate

First recorded in 1620–30; active + -ate ¹

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Explanation

To activate something is to start it off, trigger it, or set it in motion. A villain in a late-night movie might say, “Activate the robot chickens!” And then you’re free to activate your remote and change the channel. To activate something is to make it active. It’s not just for bad guys — when you activate a credit or library card, you can start using it. When a coach activates a player on a sports team, the player enters the game. If someone activates a bomb, you should run. If the pancakes you’re cooking burst into flames, you’ll probably activate the smoke alarm. And you should run.

Example Sentences

See Examples For:

activate activates activated activating

These modifications make portions of DNA more accessible, allowing cells to activate genes involved in tissue regeneration.

From Science Daily ● Nov. 8, 2026

Its new operators, Neil Biondich and Alex McCullough, are ramping up events to activate the myriad spaces inside the building, all five stories of forest-themed kitschy wonder.

From Los Angeles Times ● Nov. 6, 2026

Even after a substantial evening meal, foods rich in sugar, fat or salt can continue to activate reward pathways in the brain, helping explain why many people find themselves reaching for something more.

From BBC ● Nov. 6, 2026

If school administrators activate Google Search, they can also turn on a “guided learning mode” that detects when a student is pasting schoolwork questions into the search engine.

From The Wall Street Journal ● Nov. 3, 2026

When the leader won a set of points in this manner, she could “give birth to,” or activate, the next member of her team, who would play their counterpart on the other team.

From "Flying Through Water" by Mamle Wolo

KCL-286 activates a specific protein within this system, offering researchers a way to influence biological processes connected to brain health and cellular repair.

From Science Daily ● Nov. 3, 2026

Some radiators have a snowflake symbol on the valve that activates the frost protection setting, meaning that if the room gets very cold, the radiator warms slightly to stop the pipes from bursting.

From BBC ● Oct. 23, 2026

That is the level of dedication to this project, which becomes obvious once the ensemble activates their full powers.

From Salon ● Oct. 7, 2026

Although the model features 501 billion parameters, it only activates 23 billion parameters per query, giving users the advantage of a large, powerful model without the high computing costs.

From MarketWatch ● Oct. 5, 2026

He activates it, just like the pediatrician always did, and it flashes bright pink.

From "The Last Cuentista" by Donna Barba Higuera

By then, the Rams aim to have defensive lineman Kobie Turner activated from injured reserve.

From Los Angeles Times ● Nov. 8, 2026

When immune cells remain activated for extended periods, they can gradually lose their ability to attack cancer effectively.

From Science Daily ● Nov. 8, 2026

Taiwanese authorities activated market-stabilization measures on Friday, joining South Korea in moving to stem the bleeding in local equities caused by the global selloff in artificial intelligence-related stocks.

From The Wall Street Journal ● Nov. 6, 2026

Once activated, they can multiply and develop into muscle cells that help restore damaged tissue.

From Science Daily ● Nov. 4, 2026

“I set it up to alert me if it was activated, and it just sent me a text.”

From "City Spies" by James Ponti

If further investigations support the findings, clinical trials could eventually explore whether activating this repair mechanism benefits patients undergoing abdominal radiation therapy.

From Science Daily ● Nov. 8, 2026

It also will alert them to look for a communication from the Treasury Department with information about activating the account and receiving the $1,000 contribution, if the child is eligible.

From MarketWatch ● Oct. 21, 2026

For younger motorists, the first move when getting behind the wheel is to override the in-car infotainment system, including the radio, by activating Apple CarPlay or Android Auto.

From Slate ● Oct. 20, 2026

The Netherlands hopes to insulate the court by activating the European Union’s “blocking statute,” a rule that would ban EU companies from complying with the sanctions and thereby expose them to U.S. secondary sanctions.

From The Wall Street Journal ● Oct. 14, 2026

The first Stormbreakers would have already begun leaving the plant, and in less than twenty-four hours the prime minister would be activating them.

From "Stormbreaker" by Anthony Horowitz

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