act

1 of 5

noun

1
a
: 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
5
a
: 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

act

2 of 5

verb

acted; acting; acts

intransitive verb

1
: to take action : move
think before acting
acted favorably on the recommendation
2
: to conduct oneself : behave
act like a fool
3
a
: 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

1
a
: 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
actability noun
actable adjective

act

3 of 5

abbreviation (1)

1
active
2
actor
3
actual

ACT

4 of 5

abbreviation (2)

1
Action for Children's Television
2
Association of Classroom Teachers
3
Australian Capital Territory
used for a standardized achievement test to evaluate suitability for college admission
Phrases
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

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
Trending on Billboard This marks the first time that two of the chairs will be occupied by country acts, leading the way for some heavy competition for country contestants between Dan + Shay and McEntire. Melinda Newman, Billboard, 23 Feb. 2024 Ohio operates youth prisons in Circleville, Massillon and Highland Hills for about 470 youths ages 12 to 21 found responsible for felony acts. Laura A. Bischoff, The Enquirer, 23 Feb. 2024 Emma Stone Will Never Joke About Her Friend Taylor Swift Again: ‘What a Dope’ Swift took the stage just after 7:50 p.m. local time, according to the Sydney Morning Herald, and her support act Sabrina Carpenter didn't perform due to the weather delay. Becca Longmire, Peoplemag, 23 Feb. 2024 Nearly 150 music acts will be part of the 2024 Louder than Life festival. Marina Johnson, The Courier-Journal, 23 Feb. 2024 Simple, unexpected acts can create a ripple effect of positivity. Womensmedia, Forbes, 23 Feb. 2024 Those acts, and the people around them, probably thought such records had the potential to hook them up with a new and different group of fans. David Browne, Rolling Stone, 23 Feb. 2024 Between the racial and social unrest in 2020 and 2022, seven different Black female acts — Edwards, Kennedy and Marks included — debuted on the Opry's stage. Marcus K. Dowling, USA TODAY, 23 Feb. 2024 The number of international acts staged by the company was up a whopping 50%, partially due to its acquisition of Mexican promoter OCESA. Jem Aswad, Variety, 22 Feb. 2024
Verb
Instead of plowing through obstacles with a can-do, problem-solving attitude, people begin to think and act hesitantly, with more of a cover-their-butts attitude. Bhopi Dhall and Saurajit Kanungo, Forbes, 12 Feb. 2024 Everything to Know About the Wicked Movie During the big game, the trailer for the film adaptation of Stephen Schwartz and Winnie Holzman’s Tony-winning Broadway show aired during a commercial break, showing Grande and Erivo acting in their full Wicked attire for the first time. Brenton Blanchet, Peoplemag, 12 Feb. 2024 And parents who vented on social media, wondering what would happen if their kids acted that way toward their coach. Lisa Gutierrez, Kansas City Star, 12 Feb. 2024 Twinning here is akin to that of a Russian doll’s, a suspenseful thriller acting as a framing device for an erotic film, which in turn opens up a dreamscape free of consequence and inhibition, a dark room of the mind. Aatish Taseer, New York Times, 12 Feb. 2024 Day received an Oscar nom and won a Golden Globe for her feature acting debut in 2021 for The United States vs Billie Holiday. Kimberly Nordyke, The Hollywood Reporter, 11 Feb. 2024 Vandervort noted mothers face higher standards than fathers regarding childcare, and there are gendered expectations of how mothers and fathers should act. Eric Levenson, CNN, 10 Feb. 2024 Victor Avila: In dealing with some domestic violence cases, this was a bit different because … the way Gareth Pursehouse acted in this case was more methodical. Erin Moriarty, CBS News, 10 Feb. 2024 Lee is earning his pay, acting even more ruthlessly than Xi. Doug Bandow, National Review, 10 Feb. 2024 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'act.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

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

First Known Use

Noun

14th century, in the meaning defined at sense 1a

Verb

1590, in the meaning defined at intransitive sense 2

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

Dictionary Entries Near act

Cite this Entry

“Act.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/act. Accessed 26 Feb. 2024.

Kids Definition

act

1 of 2 noun
1
: something that is done
an act of kindness
2
: the doing of something
caught in the act
3
: a law made by a governing body
an act of Congress
4
a
: one of the main divisions of a play or opera
b
: one of the parts of a variety show or circus
5
: a display of behavior that is not sincere
just putting on an act

act

2 of 2 verb
1
: to perform by action especially on the stage
2
: to play the part of
act the man of the world
3
a
: to behave in a manner suitable to
act your age
b
: to conduct oneself
act like a fool
4
: to take action : move
think before you act
5
a
: to perform a function : serve
act as mayor
b
: to produce an effect : work
wait for a medicine to act
Etymology

Noun

Middle English act "act, deed," from Latin actus "action of doing" and from Latin actum "something done," both from agere "to drive, do" — related to agent

Medical Definition

act

1 of 3 noun
1
: a motor performance leading to a definite result
2
: a dealing with objects (as by moving, perceiving, or desiring them)

act

2 of 3 intransitive verb
1
: to perform an act : behave
2
: to produce an effect
wait for a medicine to act

act

3 of 3 abbreviation
active

Legal Definition

act

1 of 2 noun
1
a
: 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

2
a
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

2 of 2 intransitive verb
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
actor noun

More from Merriam-Webster on act

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