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

ACT

trademark
\ 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

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

Erik Lamela also got in on the act after a delicious cross from Harry Kane - all this in just the first half. SI.com, "Tottenham 4-0 Crystal Palace: Report, Ratings & Reaction as Spurs' First Half Masterclass Earns Win," 14 Sep. 2019 They are more offended by truthful words than the acts of their political ideology that has killed millions of innocent victims. Grace Segers, CBS News, "Ad showing Ocasio-Cortez's face in flames and pile of skulls airs during debate," 13 Sep. 2019 On one hand, 99 percent of species listed under the act have avoided extinction. Shawn Regan, National Review, "The New Endangered-Species Regulations Are Good for Species," 12 Sep. 2019 In the course of the investigation, the suspect was observed on an university security camera allegedly committing the act a second time. al, "2nd USA student in a week charged with terrorist threat," 12 Sep. 2019 On last night's semifinals results show, the top three acts were announced early on. Kayla Keegan, Good Housekeeping, "'AGT' Twitter Is Fuming About the “Unbelievable” and “Disappointing” Semifinal Results," 12 Sep. 2019 The troupe also will be the opening act at this year's America's Thanksgiving Day Parade in downtown Detroit. Julie Hinds, Detroit Free Press, "They did it! Detroit Youth Choir will compete next week in 'America's Got Talent' finals," 12 Sep. 2019 As often happens, the mere act of giving this pattern of behavior a name has the effect of rendering it suspect, if a bit lame. Hua Hsu, The New Yorker, "Instagram, Facebook, and the Perils of “Sharenting”," 11 Sep. 2019 While representatives for Lopez and the NFL did not respond to EW’s requests for comment, multiple outlets are reporting that the Hustlers star is close to a deal locking her in as the headlining act for next year’s big game in Miami. Sydney Bucksbaum, EW.com, "Is Jennifer Lopez going to be the 2020 Super Bowl halftime show performer?," 11 Sep. 2019

Recent Examples on the Web: Verb

Fantasies of competence are often destroyed on the awards-show stage; musical acts comfortable in the Instagram square have a hard time adjusting to the auditorium. Doreen St. Félix, The New Yorker, "Normani and the Work of the Pop Princess," 1 Sep. 2019 Houstonians looking to soak up the blue water should act fast, as it's known not to stick around long. Rebecca Hennes, Houston Chronicle, "Blue water returns to Galveston Island just in time for Labor Day weekend," 30 Aug. 2019 The committee should not act as a third-party payer, the letter states, and should instead reimburse HW&Co. directly. Courtney Astolfi, cleveland.com, "Cuyahoga County Board of Elections questions Budish campaign’s use of $208K for legal fees," 30 Aug. 2019 Pierre acted as skipper on the two-week journey across the Atlantic Ocean. Stephanie Petit, PEOPLE.com, "Meghan Markle's Environmentalist Champion Greta Thunberg, 16, Sails into NYC — with Another Royal!," 29 Aug. 2019 On the heels of record 2018 precipitation, winter and spring rain acted like gasoline, loading the bay with nutrients that cause algae to blossom. Scott Dance, baltimoresun.com, "Record rain + heat = Chesapeake Bay dead zone among biggest in decades. Crabs, fish are suffocating.," 29 Aug. 2019 The Board recently acted to repudiate $6 billion in general obligation debt (which is traditionally honored by all states without default) and attempted to claw back prior bond payments. James Spiotto For Cnn Business Perspectives, CNN, "Puerto Rico's financial woes are hurting US infrastructure," 29 Aug. 2019 With currently 39 percent under contract or reserved, those interested in the available units should act quickly. Kelli Williams, The Denver Post, "Your new oasis awaits at Uptown 240, an amenity-rich community located in Dillon," 29 Aug. 2019 But like every step before it, Ocando prevailed. His fight continued and since then, Ocando has acted as a legal consultant for the Venezuelan soccer league, Go Pro Sports Management and now teaches sports law at Florida Global University. Drake Hills, azcentral, "Phoenix Rising FC helps sports lawyer from Venezuela embrace new home in Tempe," 27 Aug. 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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Statistics for act

Last Updated

17 Sep 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 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

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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