act

noun
\ ˈakt How to pronounce act (audio) \

Definition of act

 (Entry 1 of 5)

1a : the doing of a thing : deed an act of courage
b law : something done voluntarily
2 : the process of doing something : action caught in the act
3 : the formal product of a legislative body : statute an act of Congress also : a decision or determination of a sovereign, a legislative council, or a court of justice
4 : one of the principal divisions of a theatrical work (such as a play or opera) a play in three acts
5a : one of successive parts or performances (as in a variety show or circus) a magic act
b : the performer or performers in such an act a two-person comedy act
c : a performance or presentation identified with a particular individual or group They took their act on the road.
d : the sum of a person's actions or effects that serve to create an impression or set an example a hard act to follow
6 : a display of affected behavior : pretense put on an act that deceived nobody His friendly concern was just an act.
7 often capitalized : a formal record of something done or transacted
8 : a state of real existence rather than possibility
into the act or in on the act
: into an undertaking or situation as an active participant saw the success they were having and wanted to get in on the act

act

verb
acted; acting; acts

Definition of act (Entry 2 of 5)

intransitive verb

1 : to take action : move think before acting acted favorably on the recommendation
2 : to conduct oneself : behave act like a fool
3a : to perform on the stage began acting at the age of eight
b : to behave as if performing on the stage : pretend seemed angry but was just acting
4 : to perform a specified function : serve trees acting as a windbreak
5 : to produce an effect : work wait for a medicine to act
6 : to give a decision or award adjourned without acting on the bill
7 of a play : to be capable of being performed a play that acts well

transitive verb

1a : to represent or perform by action especially on the stage will act the part of Romeo in tonight's play
b : feign, simulate act indifference
2 : to play the part of as if in a play act the man of the world
3 : to behave in a manner suitable to Act your age.
4 obsolete : actuate, animate

act

abbreviation (1)

Definition of act (Entry 3 of 5)

1 active
2 actor
3 actual

ACT

abbreviation (2)

Definition of ACT (Entry 4 of 5)

1 Action for Children's Television
2 Association of Classroom Teachers
3 Australian Capital Territory
\ ˌā-ˌsē-ˈtē How to pronounce ACT (audio) \

Definition of ACT (Entry 5 of 5)

used for a standardized achievement test to evaluate suitability for college admission

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Other Words from act

Verb

actability \ ˌak-​tə-​ˈbi-​lə-​tē How to pronounce actability (audio) \ noun
actable \ ˈak-​tə-​bəl How to pronounce actable (audio) \ adjective

Synonyms for act

Synonyms: Noun

Synonyms: Verb

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Examples of act in a Sentence

Noun We were grateful for her many acts of kindness. the Civil Rights Act of 1964 Please read act II, scene 1 of Shakespeare's Romeo and Juliet. In the first act, two characters are talking in a restaurant. Verb He knew he had to act quickly. The government was slow to act. She acted on behalf of her father, who was not at the meeting. I believe that the killer acted alone. She had acted in self-defense when she killed her attacker. We were acting in the best interests of our children. We must act soon to end this crisis. She learned at an early age how to act properly in social situations. People are always telling me how I should act and what I should say. I noticed that the dog was acting funny this morning.
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Recent Examples on the Web: Noun But the act has never been used to end a military conflict. Dustin Gardiner, SFChronicle.com, "Bay Area lawmakers slam Trump for drone strike that killed Iranian general," 3 Jan. 2020 But there was more to this perception than the simple act of reading texts. Time, "Why the U.S. Sent Librarians Undercover to Gather Intelligence During World War II," 3 Jan. 2020 The 50 or so pages of revisions that the Council on Environmental Quality is expected to make public on Wednesday would not amend the act itself. Lisa Friedman, New York Times, "Trump Rule Would Exclude Climate Change in Infrastructure Planning," 3 Jan. 2020 Even DeRozan — a player famously allergic to the 3-point line — has gotten into the act. Jeff Mcdonald, ExpressNews.com, "LaMarcus Aldridge, Spurs finding better things coming in threes," 3 Jan. 2020 Pushed by foster care alumni, the act also aims to restrict federal spending for group homes and other congregate care facilities that house six or more children. Washington Post, "‘We are just destroying these kids’: The foster children growing up inside detention centers," 31 Dec. 2019 The simple act of watching in 3D caused eye strain in a significant chunk of the population. Brian Barrett, Wired, "3D TV Tells You Everything About This Decade’s Tech," 31 Dec. 2019 Whether in the old days or now, impeachment happens when the Senate is presented with the act of impeachment — which triggers the trial, as the Senate rules say. Noah Feldman, Twin Cities, "Noah Feldman: If Trump’s impeached, then why can’t a Senate trial start now?," 30 Dec. 2019 Dayan called on leaders at every level, from college campuses to the federal government, to speak out against the acts. Anchorage Daily News, "Jewish leaders urge action after another ‘senseless’ attack," 30 Dec. 2019 Recent Examples on the Web: Verb State officials have so far declined to act on that order. cleveland, "Population estimates show Flyover states will lose influence following 2020: The Flyover," 6 Jan. 2020 But most countries have been slow to act on their promises. Davide Castelvecchi, Scientific American, "Watch Out for These Science Events in 2020," 30 Dec. 2019 Tetra sidesteps 2006’s Colorado Indoor Clean Air Act, which banned smoking in most public, indoor spaces, by acting as a private club that sells daily memberships for $20 a pop (or $60 per month). John Wenzel, The Know, "Starting Jan. 1, Coloradans will have more options for consuming cannabis in public. But will we catch up to California?," 27 Dec. 2019 The notion that employees are entitled to distraction-free lives outside work—like most other values companies cultivate over time—has to come straight from the top, or no one will act on it. Anne Fisher, Fortune, "Most People Will Be Working During the Holidays Because They Can," 26 Dec. 2019 The transcript of Patterson's interview paints a picture of a man who acted on impulse and controlled Jayme's movements around the cabin where she was held more than an hour away from her family home. Fox News, "Jayme Closs' captor manipulated her, admitted to having sexual fantasies of the teen, new documents reveal," 22 Dec. 2019 The American Civil Liberties Union of Ohio, acting on behalf of the New Prospect Baptist Church, brought the case to the appellate court in a bid to upend the county's ban on homeless encampments that has been in place since 2018. Erin Glynn, Cincinnati.com, "Hamilton County ban on homeless camps partially overturned by state appeals court," 20 Dec. 2019 The transcript of Patterson’s interview paints a picture of a man who acted on impulse and controlled Jayme’s movements around the cabin where she was held in northwestern Wisconsin. Amy Forliti, Twin Cities, "In police interviews, kidnapper believed Jayme Closs would never escape. He was wrong.," 20 Dec. 2019 In Louisiana, Scott Sutterfield left his position in September as acting director of ICE’s field office in New Orleans and immediately took an executive position at LaSalle Corrections. USA Today, "'These people are profitable': Under Trump, private prisons are cashing in on ICE detainees," 20 Dec. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'act.' 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 act

Noun

14th century, in the meaning defined at sense 1a

Verb

1590, in the meaning defined at intransitive sense 2

History and Etymology for act

Noun

Middle English acte, borrowed from Anglo-French & Latin; Anglo-French acte, act, borrowed partly from Latin āctus "driving of cattle, track for cattle, movement, activity, performance, part of a play" (action noun from agere "to drive (cattle), cause to move, do"), partly from Latin āctum (usually in plural) "thing done, public transaction, record," from neuter of āctus, past participle of agere — more at agent

Verb

Middle English acten "to act upon, adjudicate," in part derivative of act act entry 1, in part borrowed from Latin āctus, past participle of agere

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Time Traveler for act

Time Traveler

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

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Statistics for act

Last Updated

8 Jan 2020

Cite this Entry

“Act.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/act. Accessed 21 January 2020.

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More Definitions for act

act

noun
How to pronounce ACT (audio)

English Language Learners Definition of act

 (Entry 1 of 2)

: something that is done
: a law made by a group of legislators
: one of the main divisions of a play or opera

act

verb

English Language Learners Definition of act (Entry 2 of 2)

: to do something : to take action
: to behave in a particular way
: to behave in a way that is not sincere or honest

act

noun
\ ˈakt How to pronounce act (audio) \

Kids Definition of act

 (Entry 1 of 2)

1 : something that is done : deed an act of bravery
2 : a law made by a governing body
3 : a main division of a play
4 : one of the performances in a show a juggling act
5 : an insincere way of behaving Her crying was just an act.

act

verb
acted; acting

Kids Definition of act (Entry 2 of 2)

1 : to do something : move It's important to act quickly in an emergency.
2 : to behave oneself in a certain way He's been acting strangely.
3 : to perform as a character in a play Both stars agreed to act in the movie.
4 : to perform a certain function She'll act as our guide.
5 : to have a result : make something happen : work The medicine acts on the heart.
act up
: to behave badly

act

noun
\ ˈakt How to pronounce act (audio) \

Medical Definition of act

 (Entry 1 of 3)

1 : a motor performance leading to a definite result
2 : a dealing with objects (as by moving, perceiving, or desiring them)

Medical Definition of act (Entry 2 of 3)

1 : to perform an act : behave
2 : to produce an effect wait for a medicine to act

Medical Definition of act (Entry 3 of 3)

active

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act

noun

Legal Definition of act

 (Entry 1 of 2)

1a : something done by a person in accordance with his or her free will a tortious act — see also actus reus
b : the failure to do something that one has a legal duty to do

called also negative act

2a often capitalized : the formal product of a legislative body : the formally declared will of a legislature the final requirement of which is usually the signature of the proper executive officer : statute an act of Congress in furtherance of the purposes…of that actU.S. Code
b : a decision or determination of a sovereign, a legislative council, or a court of justice — compare bill sense 1
3 often capitalized : a formal record of something done or transacted given as my free act and deed

Legal Definition of act (Entry 2 of 2)

1 : to carry into effect a determination of the will : take action
2 : to discharge the duties of a specified office or post : perform a specified function used with a prepositional phrase declaring what officer shall then act as PresidentU.S. Constitution art. II
3 : to give a decision or award (as by vote of a deliberative body or by judicial decree) often used with on adjourned with several important matters still not acted on

Other Words from act

actor \ ˈak-​tər How to pronounce actor (audio) \ noun

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More from Merriam-Webster on act

Thesaurus: All synonyms and antonyms for act

Rhyming Dictionary: Words that rhyme with act

Spanish Central: Translation of act

Nglish: Translation of act for Spanish Speakers

Britannica English: Translation of act for Arabic Speakers

Comments on act

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