activate

verb

ac·​ti·​vate ˈak-tə-ˌvāt 

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

ˌak-tə-ˈvā-shən 

noun

activator

ˈak-tə-ˌvā-tər 

noun

Synonyms

• actuate
• crank (up)
• drive
• move
• run
• set off
• spark
• start
• touch off
• trigger
• turn on

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

Roberts said Buehler probably would need to reach 90 pitches — and make three more minor league starts — before the Dodgers consider activating him. —Bill Shaikin, Los Angeles Times, 1 Apr. 2024

Amazon’s Echo Shows have their own special tricks and ways to activate them. —Nena Farrell, WIRED, 29 Mar. 2024

Researchers use music in therapy for Alzheimer's and dementia patients because specific songs and tunes may help activate memories. —Suzanne Nuyen, NPR, 29 Mar. 2024

The real issue is not knowing how to engage, activate and retain the employees already on their teams. —Raphael Crawford-Marks, Forbes, 28 Mar. 2024

Start a Movement For its Music of the Spheres tour, Coldplay deployed a kinetic dancefloor, harnessing the crowd’s movement to activate LED lights and other visuals — and to generate electricity that was then routed to power elements of the production. —Dave Brooks, Billboard, 28 Mar. 2024

The Army Corps of Engineers has activated its emergency operations center following the collapse, authorizing more than 1,100 personnel to support recovery efforts and clear the busy shipping channel of debris, the Army announced Tuesday. —Minnah Arshad, USA TODAY, 27 Mar. 2024

The Ebony Alert, which stemmed from legislation passed in 2024, is activated to help find missing Black children and young Black women. —Ishani Desai, Sacramento Bee, 25 Mar. 2024

Think zinc In addition to increasing the output of white blood cells, zinc plays an active role in bolstering the immune system by activating enzymes that break down proteins found in viruses and bacteria. —Georgia Day, Vogue, 16 Mar. 2024

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

Kids Definition

activate

verb

ac·​ti·​vate ˈak-tə-ˌvāt 

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

ˌak-tə-ˈvā-shən 

noun

activator

ˈak-tə-ˌvāt-ər 

noun

Medical Definition

activate

transitive verb

ac·​ti·​vate ˈak-tə-ˌvāt 

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

ˌak-tə-ˈvā-shən 

noun