act

noun
\ ˈakt \

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

ACT

trademark
\ ˌā-ˌsē-ˈtē\

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 \ noun
actable \ ˈak-​tə-​bəl \ adjective

Synonyms for act

Synonyms: Noun

bit, number, routine, shtick (also schtick), turn

Synonyms: Verb

do, impersonate, interpret, perform, play, portray

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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

Giving yourself as much time as possible to sort out the logistics is really an act of kindness. Korin Miller, SELF, "6 Different End-of-Life Care Options to Know if You or a Loved One Is Sick," 18 Dec. 2018 Blind recruitment is the act of removing name, gender, age and educational background from applications to reduce bias and improve diversity. Diya Khanna, The Seattle Times, "Would you hire me if you were blindfolded?," 20 Nov. 2018 New research from the University of Sussex in England echoes this, suggesting that smiling is more an act of engagement with people than an expression of inner joy. Loren Savini, Allure, "Does Smiling Cause Wrinkles? No, and "Resting Bitch Face" Doesn't Prevent Them," 10 Oct. 2018 Second, the space agency wanted to affirm its view that this was likely not an intentional bit of sabotage—and definitely was not an act of NASA astronauts in space. Eric Berger, Ars Technica, "After more speculation about cause of ISS leak, NASA issues another statement," 3 Oct. 2018 What that became, though, that plus the combination of some legislative things, like Communications Decency Act, section 230, that act was created so that they were indemnified from the content on their platform. Recode Staff, Recode, "Full transcript: Data for Democracy policy head Renée DiResta answers disinformation questions on Too Embarrassed to Ask," 14 July 2018 Even his more overtly emotional movies don’t play like acts of soul-baring. Jesse Hassenger, The Verge, "Welcome to Marwen is Robert Zemeckis’ most revealing movie — and his worst," 20 Dec. 2018 The emerging profile pointed to an increasingly common hybrid extremist who moves from acts of delinquency to sowing terror. Elaine Ganley, The Seattle Times, "Gunman from Christmas market attack in France still at large," 12 Dec. 2018 Shonda thanked Serena for being an exceptional athlete, and overall human, who stands up against acts of hatred and ignorance. Harleen Sidhu, Teen Vogue, "10 Celebrities on How Serena Williams Inspires Them," 12 Dec. 2018

Recent Examples on the Web: Verb

In 2018, amid an ongoing affordable housing, prefab manufacturer LivingHomes dove deeper into accessory dwelling units (ADUs), introducing compact designs that can act as a spare room in the backyard or a standalone tiny home. Jenny Xie, Curbed, "The 7 most impressive prefab homes from 2018," 27 Dec. 2018 To give you some background, candles are usually made from paraffin wax or soy wax, both of which are solids that act as the fuel for candle flame. Sam Gutierrez, House Beautiful, "Are Your Favorite Candles Slowly Poisoning You?," 26 Dec. 2018 Although Molly is usually behind-the-scenes, this isn't her only acting credit. Jennifer Aldrich, Country Living, "Did You Recognize Jimmy Kimmel's Wife Molly McNearney in 'Dumplin''?," 15 Dec. 2018 Apparently the monster slayer himself, Geralt of Rivia, will arrive in Monster Hunter: World sometime in early 2019, along with new voice acting by Doug Cockle. Hayden Dingman, PCWorld, "This week in games: Heroes of the Storm winds down, Monster Hunter adds The Witcher's Geralt," 14 Dec. 2018 Herrington comes from the Amazon Retail side of the business, where Amazon sources products itself and acts as a seller. Jason Del Rey, Recode, "An Amazon revolt could be brewing as the tech giant exerts more control over brands," 29 Nov. 2018 As Xi gets into his sixth year of presidency and China’s internet regulator grows more centralized, acts like these feel more elusive and fleeting. Shannon Liao, The Verge, "2018 was the year Chinese internet users evaded censorship — briefly," 20 Dec. 2018 But South Sudan's government already struggles to support existing teams including ones for soccer, basketball and handball, said Josseline Samson Apaya, acting director general for sports in the ministry of sports, culture and youth. Sam Mednick, Fox News, "War-torn South Sudan launches youth rugby league for peace," 28 Sep. 2018 The documents show that Whitaker began revising his public disclosures the day he was appointed acting attorney general. Chad Day, The Seattle Times, "Right-leaning nonprofit paid Whitaker nearly $1 million," 21 Nov. 2018

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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Statistics for act

Last Updated

14 Jan 2019

Look-up Popularity

Time Traveler for act

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

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More Definitions for act

act

noun

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 \

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 \

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 \ noun

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More from Merriam-Webster on act

Rhyming Dictionary: Words that rhyme with act

Thesaurus: All synonyms and antonyms for 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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