ac·​tion | \ˈak-shən \
plural actions

Definition of action 

1a : 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 actions plural : behavior, conduct unscrupulous actions

d : initiative, enterprise a man of action

2 : an act of will an emergency requiring action

3 : the bringing about of an alteration by force or through a natural agency the action of water on rocks

4 : the manner or method of performing:

a : an actor's or speaker's deportment or expression by means of attitude, voice, and gesture An actor's words and actions should agree.

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

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

6a(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 Most of the play's action takes place in a courtroom.

(2) : the unfolding of the events of a drama or work of fiction : plot As the action unfolds, we learn more about the hero's family.

(3) : the movement of incidents in a plot a movie that is two hours of nonstop action

c : the combination of circumstances that constitute the subject matter of a painting or sculpture

7a : an operating mechanism

b : the manner in which a mechanism or instrument operates a drill's twisting action

8a : 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 : sexual activity

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

11 used as a director's command to start filming part of a movie or television show Lights, camera, action!

12 : spin or rotation given to a ball or puck by throwing or hitting it in a particular way If I am hitting into the wind on the 7th at Pebble Beach, … rather than taking an eight or a nine [iron] and hitting it hard, I'll choose a little eight or even a seven and almost chip the ball, putting as little action on it as possible so it lands softly and doesn't do a lot of spinning.— Jack Nicklaus

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Synonyms for action


act, deed, doing, exploit, feat, thing

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Examples of action in a Sentence

He was critical of the government's actions before the war. a military action against another country She tried to explain her actions. I accept full responsibility for my actions. The situation demanded immediate action. The problem may require military action. The school took disciplinary action against the drunken students. They decided that no further action was necessary.
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Recent Examples on the Web

In the Devil’s Snare with an eye toward explaining the crisis in its historical and political context, connected the hysteria over the witch trials and the actions taken by village elders to Native American attacks on the New England settlers. Dylan Scott, Vox, "“Witch hunts” explained, from Salem to Donald Trump," 8 Dec. 2018 This happens, Pandurangi says, because antipsychotics interfere with and diminish the action of insulin on glucose (sugar). Kimberly Truong, SELF, "11 Side Effects of Antipsychotics You Should Know About," 7 Dec. 2018 Kate Middleton and Prince William have had their share of Christmas activities this week, but Meghan Markle and Prince Harry also got in on the holiday action behind the scenes. Erica Gonzales, Harper's BAZAAR, "Meghan Markle and Prince Harry Secretly Attended a Christmas Reception Together," 7 Dec. 2018 To lower the action, simply turn each saddle screw clockwise with an Allen wrench. Henry Robertson, Popular Mechanics, "How to Set Up a Guitar And Make It Your Own," 7 Dec. 2018 However, the system has changed; now, the private inspectors report directly to the city if the unit passed or failed, constituting a state action and, according to the suit, a privacy violation. Patrick Sisson, Curbed, "Seattle’s mandatory rental inspection law challenged in lawsuit," 6 Dec. 2018 The action continues on Wednesday, with the launch of another Falcon 9 rocket carrying the Dragon spacecraft into orbit, scheduled for 1:16pm ET (18:16pm UTC). Eric Berger, Ars Technica, "SpaceX launches 2.5 tons of cargo to the ISS, but … [Updated]," 5 Dec. 2018 But now veteran coach Adam wants fellow star Kelly Clarkson to get in on the action, too. Megan Stein, Country Living, "Adam Levine Wants Kelly Clarkson to 'Stomach Punch' Blake Shelton on 'The Voice'," 4 Dec. 2018 We will be surrounded by the consequences of our actions — thousands of tiny, resistant, evasive cockroaches, bed bugs, lice, houseflies and fleas. Rob Dunn, Discover Magazine, "Our Attempts to Eradicate Insects are Just Making them Resistant to Pesticides," 16 Nov. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'action.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of action

14th century, in the meaning defined at sense 5

History and Etymology for action

Middle English accioun, borrowed from Anglo-French accion, borrowed from Latin āctiōn-, āctiō "activity, act, legal process," from agere "to drive (cattle), cause to move, do" + -tiōn-, -tiō, noun suffix of verbal action — more at agent

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Statistics for action

Last Updated

13 Dec 2018

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Time Traveler for action

The first known use of action was in the 14th century

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More Definitions for action


ac·​tion | \ˈak-shən \

Kids Definition of action

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

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

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

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

5 : combat in war


ac·​tion | \ˈak-shən \

Medical Definition of action 

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 : 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 : an act of will

4 actions plural : behavior aggressive actions



Legal Definition of action 

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

History and Etymology for action

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

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More from Merriam-Webster on action

Rhyming Dictionary: Words that rhyme with action

Thesaurus: All synonyms and antonyms for action

Spanish Central: Translation of action

Nglish: Translation of action for Spanish Speakers

Britannica English: Translation of action for Arabic Speakers Encyclopedia article about action

Comments on action

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


living or existing for a long time

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