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

Definition of act (Entry 3 of 5)

1 active
2 actor
3 actual

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 ACT (audio) \ noun
actable \ ˈak-​tə-​bəl How to pronounce ACT (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 Harrison performed her act for a room full of chairs, some propping up cardboard cutouts, with only two writers present to call out any audience reactions that were written into the script. Nojan Aminosharei, Harper's BAZAAR, "No One Does It Like Patti Harrison," 31 Dec. 2020 The love affair with Herman has gradually tapered off since the Longhorns followed his opening act with a Sugar Bowl win in 2018. Nick Moyle, ExpressNews.com, "Could Alamo Bowl win build momentum for Tom Herman and Texas?," 30 Dec. 2020 Plus, the singer will drop some special surprises throughout his act. Darlene Aderoju, PEOPLE.com, "Sneak a Peek Inside Justin Bieber's New Year's Eve Rehearsals Before Secret Venue Is Revealed," 30 Dec. 2020 February was likely the most important month for global health agencies and governments to get their act together to quell the pandemic. Sy Mukherjee, Fortune, "Timeline: From the first coronavirus cases to the first vaccinations," 30 Dec. 2020 But the biggest question in Hollywood is will consumers return to the cineplex once vaccines hit critical mass, or have the glory days of going the movies reached their final act? Cnn Business Staff, CNN, "2020's biggest winners and losers in business," 30 Dec. 2020 One sign of how thoroughly Chatroulette has cleaned up its act: an embryonic corporate conference business. Kevin Randall, Wired, "Chatroulette Is On the Rise Again—With Help From AI," 26 Dec. 2020 The Save Our Stages act is aimed at helping only those venues that have already closed or are at risk of shutting down. Matthew Brown, USA TODAY, "'Three-martini lunch' tax break, foreign aid: Why year-end bills are stirring controversy," 25 Dec. 2020 Tyler Lockett continued his disappearing act during the second half of the season here. Eddie Brown, San Diego Union-Tribune, "Fantasy Football Week 16: Start and Sit (Championship Edition)," 25 Dec. 2020 Recent Examples on the Web: Verb The foremost one, the article states, is to explain that the violence was an attack on the country and its democratic institutions, but that communities are coming together to stand up against those who incite and act on violence. Annie Vainshtein, SFChronicle.com, "How to talk to your kids about the U.S. Capitol riots," 7 Jan. 2021 The council, composed of House and Senate leaders, says the appointments Dunleavy presented in early 2020 lapsed in December after lawmakers failed to act on them. From Usa Today Network And Wire Reports, USA TODAY, "Hank Aaron, skeptic’s mea culpa, vaccine campouts: News from around our 50 states," 6 Jan. 2021 Davies is less interested in the bourgeois fabric of life—where McLaughlin is like Ibsen, whose plays are cluttered with objects, Davies is closer to Chekhov, whose characters act on a near-empty stage. Claire Messud, Harpers Magazine, "New Books," 5 Jan. 2021 In that case, 21 youths alleged that the federal government, by failing to act on climate change, had violated their rights to life, liberty, and property and failed to protect essential public trust resources. Popular Science, "A lawsuit filed by children has forced 33 countries to rethink their climate goals," 5 Jan. 2021 The council, composed of House and Senate leaders, says the appointments Dunleavy presented in early 2020 lapsed in December after lawmakers failed to act on them. Becky Bohrer, Anchorage Daily News, "Lawyers for Alaska Gov. Dunleavy want part of law on appointments tossed amid dispute with lawmakers," 5 Jan. 2021 During their conversation, Trump accused Raffensperger of being aware of election integrity issues with his Nov. 3 contest but refusing to act on them, according to audio obtained by the Washington Post. Naomi Lim, Washington Examiner, "'Disgraceful': Biden transition lawyer skewers Trump over reported Georgia election phone call," 3 Jan. 2021 Even before then, Chinese doctors and scientists had been pushing for answers, yet officials in Wuhan and Beijing concealed the extent of infections or refused to act on warnings. New York Times, "25 Days That Changed the World: How Covid-19 Slipped China’s Grasp," 1 Jan. 2021 If physicians were ready to use that information, and patients were ready to act on it, then investing the $1,000 [the going commercial rate] to sequence any of our genomes would be trivial in the grand scheme of our medical care for life. Megan Molteni, Wired, "30 Years Since the Human Genome Project Began, What’s Next?," 30 Dec. 2020

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

14 Jan 2021

Cite this Entry

“Act.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/act. Accessed 21 Jan. 2021.

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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 act (audio) \ noun

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More from Merriam-Webster on act

Thesaurus: All synonyms and antonyms for act

Nglish: Translation of act for Spanish Speakers

Britannica English: Translation of act for Arabic Speakers

Comments on act

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