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

Here’s hoping that his first act as sheriff will be figuring out where the hell Child Protective Services is in this town. Emma Dibdin, Harper's BAZAAR, "Can Riverdale Please Be "Bizarrodale" Every Week?," 7 Feb. 2019 Synthwave gained momentum in the early 2010s, but only in recent years have its acts reached bigger audiences. Neil Shah, WSJ, "Synthwave, the Sound of an ’80s Childhood, Goes Mainstream," 26 Jan. 2019 Amazon looked magnanimous in the moment, but its act was colored by months of fighting and the caveats on pay increases that came next. Jacob Kastrenakes, The Verge, "The Verge 2018 tech report card: Amazon," 27 Dec. 2018 Scott has proven to be a generous soul in the music industry and his latest act of altruism is a true testament to that fact. Brooke Bobb, Vogue, "Travis Scott Played Fashion Santa to Seniors at This Houston High School," 18 Dec. 2018 Elaine May Elaine May rose to fame alongside her comedic partner Mike Nichols, though their dual act only lasted a few years. Chloe Foussianes, Town & Country, "The Marvelous Mrs. Maisel," 16 Dec. 2018 The frustration is also fueled by the vision of what could have been if the manufacturer had truly gotten its act together. Eric Bangeman, Ars Technica, "Love the hardware, hate the UI: The Acura MDX Sport Hybrid," 13 Dec. 2018 Watch how his small but impactful acts have helped perk up New Orleans—and get inspired to do more for your neighborhood! Stacia Affelt, Country Living, "How Anyone Can Make a Difference in Their Local Community," 6 Nov. 2018 Again, in America, hundreds of thousands of women are now attempting this dangerous act. Jennifer Wright, Harper's BAZAAR, "Anti-Abortion Activists Are Still Defending Forced Birth with Debunked Science," 26 Jan. 2019

Recent Examples on the Web: Verb

Larry Busacca The actress, comedian, writer, singer, and producer started her career performing stand-up comedy and acting in off-Broadway productions in the 1960s. Marie Claire, "Lily Tomlin Gets Candid About Her Biggest Career Regret," 11 Feb. 2019 But the dialogue, staging, and acting in this subplot were some of the weakest of the show. Darren Orf, Popular Mechanics, "'Star Trek: Discovery' Is All About Friendship and Death This Week," 8 Feb. 2019 In both their personal and professional lives, Ouellette and Vandal have championed little-known and emerging creatives, acting as ambassadors for young talent, and then utilizing those works to elevate their own. Jennifer Fernandez, House Beautiful, "This Montreal Couple Designed a Whole House Around the Art," 6 Feb. 2019 Though his acting record is impressive, what’s even more important is his sweet relationship with Molly. Megan Stein, Country Living, "'Last Man Standing' Star Molly McCook Has a Famous Father You'll Totally Recognize," 2 Feb. 2019 Gaga has been characterized as an underdog, a Hollywood newcomer, for her breakout role in A Star Is Born (despite being a global superstar and winning a Golden Globe for acting in 2015). Kyndall Cunningham, Glamour, "The Oscar Race Is All About Gaga vs. Glenn—But What About Women of Color?," 22 Jan. 2019 Those 50ish minutes serve as a mini model of how the patient acts in the real world. SELF, "How Can You Tell if Therapy Is Actually Working?," 11 Dec. 2018 Climate change is a classic tragedy of the commons: every country acting in its own self-interest contributes to depleting a joint resource, making the world worse for everyone. Cathleen O'grady, Ars Technica, "The US would suffer some of the biggest costs of climate change," 30 Sep. 2018 John Paulson, for example, invested inOneWest Bank, the lender rehabilitated by executives that included Treasury Secretary Steven Mnuchin and Joseph Otting, acting chief of Fannie and Freddie’s federal regulator. Andrew Ackerman, WSJ, "Popular Hedge Fund Bet on Fannie and Freddie Is Paying Off Big This Year," 26 Jan. 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

19 Feb 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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