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

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

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. See More
Recent Examples on the Web: Noun Naomi’s ties with the promotion are much deeper as her husband Jimmy Uso is one-third of the top act in WWE and also cousins with top WWE star Roman Reigns. Alfred Konuwa, Forbes, 16 June 2022 His administration suspended weapons sales to Saudi Arabia and the United Arab Emirates, an act of tacit disapproval of the way the Gulf monarchies had conducted the ruinous war in Yemen. Ishaan Tharoor, Washington Post, 15 June 2022 This astonishing act of hospitality meant that Ukrainian children are now learning in Polish classrooms; doctors have opened up their clinics, and private businesses offer free services to refugees. New York Times, 15 June 2022 So when a baby whale washes up on the island, Noi tries to secretly care for it at home – an act that ends up bringing him close to his dad. K.j. Yossman, Variety, 15 June 2022 Which isn’t exactly crowd-pleasing protocol for an act touring his 39th studio album. Los Angeles Times, 15 June 2022 His diagnosis midway through the season makes this final act of annihilation imminent. Josh St. Clair, Men's Health, 13 June 2022 Yet this act also ignores the climate crisis, despite the fact that hundreds of Murray’s constituents were killed last year by a 1,000-year heat wave made 150 times more likely by Anthropocene warming. David Introcaso, STAT, 13 June 2022 Generally, to be considered a lynching, an act must involve collective violence, meant to enforce a racial order. Courtney Tanner, The Salt Lake Tribune, 12 June 2022 Recent Examples on the Web: Verb Two of the people appeared to act as lookouts, while the other two smashed a display case with a crowbar, the police department reported. Kimberly Fornek, Chicago Tribune, 17 June 2022 Good leaders learn to proactively assess situations, anticipate problems that may occur and act before small issues become big problems. Ray Makela, Forbes, 17 June 2022 The study, published Tuesday in iScience, revealed that compounds of catnip (Nepeta cataria) and silver vine (Actinidia polygama) — called iridoids — can act as insect repellants. Vanessa Etienne, PEOPLE.com, 15 June 2022 Disney feels that the rights its has secured will still act as a locomotive for other content. Patrick Frater, Variety, 14 June 2022 The Panther’s turret is bigger with sharper angles and a much larger overhang over the engine compartment, the latter to both store larger, heavier main gun ammunition and to act as a counterweight to the new 130-millimeter main gun. Kyle Mizokami, Popular Mechanics, 14 June 2022 The main purpose of the new Disney+ show is to act as a bridge between one Star Wars series and the next. Grace Segers, The New Republic, 14 June 2022 The real scene-stealer in Lightyear is Sox, Buzz’s personal companion robot that happens to look and act a lot like a cat. Jacob Siegal, BGR, 13 June 2022 SpaceX will put up historic markers accordingly and act to preserve any relevant items found during construction. John Timmer, Ars Technica, 13 June 2022 See More

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.

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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Dictionary Entries Near act

ACS

act

ACT

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Statistics for act

Last Updated

19 Jun 2022

Cite this Entry

“Act.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/act. Accessed 28 Jun. 2022.

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More Definitions for act

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)

act

intransitive verb

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

act

abbreviation

Medical Definition of act (Entry 3 of 3)

active

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

act

intransitive verb

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

More from Merriam-Webster on act

Nglish: Translation of act for Spanish Speakers

Britannica English: Translation of act for Arabic Speakers

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