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noun ac·tion \ˈak-shən\

Definition of action

  1. 1 :  the initiating of a proceeding in a court of justice by which one demands or enforces one's right; also :  the proceeding itself

  2. 2 :  the bringing about of an alteration by force or through a natural agency

  3. 3 :  the manner or method of performing: a :  an actor's or speaker's deportment or expression by means of attitude, voice, and gesture b :  the style of movement of the feet and legs (as of a horse) c :  a function of the body or one of its parts

  4. 4 :  an act of will

  5. 5 a :  a thing done :  deed b :  the accomplishment of a thing usually over a period of time, in stages, or with the possibility of repetition c plural :  behavior, conduct <unscrupulous actions> d :  initiative, enterprise <a man of action>

  6. 6 a (1) :  an engagement between troops or ships (2) :  combat in war <gallantry in action> b (1) :  an event or series of events forming a literary composition (2) :  the unfolding of the events of a drama or work of fiction :  plot (3) :  the movement of incidents in a plot c :  the combination of circumstances that constitute the subject matter of a painting or sculpture

  7. 7 a :  an operating mechanism b :  the manner in which a mechanism or instrument operates

  8. 8 a :  the price movement and trading volume of a commodity, security, or market b :  the process of betting including the offering and acceptance of a bet and determination of a winner c :  financial gain or an opportunity for financial gain <a piece of the action>

  9. 9 :  sexual activity

  10. 10 :  the most vigorous, productive, or exciting activity in a particular field, area, or group <wants to be where the action is>

Examples of action in a sentence

  1. He was critical of the government's actions before the war.

  2. a military action against another country

  3. She tried to explain her actions.

  4. I accept full responsibility for my actions.

  5. The situation demanded immediate action.

  6. The problem may require military action.

  7. The school took disciplinary action against the drunken students.

  8. They decided that no further action was necessary.

Origin of action

Middle English accioun, from Anglo-French accion, from Latin action-, actio, from agere to do — more at agent

First Known Use: 14th century

Rhymes with action

ACTION Defined for Kids


noun ac·tion \ˈak-shən\

Definition of action for Students

  1. 1 :  the process by which something produces a change in another thing <the action of acid on metal>

  2. 2 :  the doing of something <Action is needed on this problem.>

  3. 3 :  something done <The mayor's first action was to call a meeting.>

  4. 4 :  the way something runs or works <the toy car's spinning action>

  5. 5 :  combat in war

Medical Dictionary


noun ac·tion \ˈak-shən\

Medical Definition of action

  1. 1:  the process of exerting a force or bringing about an effect that results from the inherent capacity of an agent <protein synthesis is an expression of gene action> <insecticidal action>

  2. 2:  a function or the performance of a function of the body (as defecation) or of one of its parts <the normal baby has three or four actions of the bowel in 24 hours—Morris Fishbein> <heart action>

  3. 3:  an act of will

  4. 4actions plural :  behavior <aggressive actions>

Law Dictionary


noun ac·tion

Legal Definition of action

  1. 1a :  a judicial proceeding for the enforcement or protection of a right, the redress or prevention of a wrong, or the punishment of a public offense — compare special proceeding at proceeding b :  the right to bring or maintain such a legal or judicial proceeding

  2. 2 :  an act or decision by an executive or legislative body of a government (as an administrative agency) or of an organization (as a Board of Directors) <the power of courts to invalidate statutes and executive actions — R. H. Bork>

  3. 3 :  a voluntary act of will that manifests itself externally :  a mode of conduct

Origin of action

Latin actio legal proceeding, from agere to do, carry out, initiate legal proceedings

Seen and Heard

What made you want to look up action? Please tell us where you read or heard it (including the quote, if possible).


the range of perception or understanding

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