activate

verb ac·ti·vate \ ˈak-tə-ˌvāt \

Definition of activate

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

play \ˌak-tə-ˈvā-shən\ noun

activator

play \ˈak-tə-ˌvā-tər\ noun

Examples of activate in a Sentence

  1. Touch the screen to activate the system.

  2. activate and then deactivate a mechanism

  3. The camera is activated by pushing a button.

  4. The bomb was activated by remote control.

  5. Sunlight activates a chemical reaction in the plant's leaves.

  6. vitamins that activate the growth of new cells

  7. The President has activated the reserves.

Recent Examples of activate from the Web

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


ACTIVATE Defined for Kids

activate

verb ac·ti·vate \ ˈak-tə-ˌvāt \

Definition of activate for Students

activated; activating
:to start working or cause to start working
  • Activate the alarm.

Medical Dictionary

activate

transitive verb ac·ti·vate \ ˈak-tə-ˌvāt \

medical Definition of activate

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 AmericanSeptember 1999
c :to make (a substance) radioactive

activation

play \ˌak-tə-ˈvā-shən\ noun


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