act

noun \ ˈakt \

Definition of act

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

— 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

See act defined for English-language learners

See act defined for kids

Examples of act in a Sentence

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.

Recent Examples of act from the Web

Even with our world's recent surge towards promoting self-love and self-acceptance, posting a selfie on Instagram can still feel like a high-wire act.

— rachel nussbaum, Glamour, "Gabrielle Union Just Celebrated Her Freckled Skin With a No-Makeup Selfie," 30 Aug. 2017
From Sonoma Mountain Winery, the breakout act from Nic Coturri, a fourth-generation winemaker, to Carignan fermented by Evan Lewandowski in Salt Lake City, domestic wine is no longer about cashing in on White Zin.

— belle cushing, Bon Appetit, "So, What Exactly Is Natural Wine?," 28 Aug. 2017
From lack of consciousness, to consciousness after the act, to consciousness before.

— rabbi avi weiss, Jewish Journal, "Weiss: Individuals engaged in acts of kindness are destined to redeem the world," 28 Aug. 2017
Yet, country acts rarely make their way as far south as Miami-Dade County.

— carli teproff, miamiherald, "Move over, salsa. Country music festival making its Miami debut.," 25 Aug. 2017
Random acts of kindness have a way of sticking with you.

— rob manker, Naperville Sun, "Manker: Mystery man gave a gift far greater than just buying ice cream," 24 Aug. 2017
Working sometimes seven days a week, her daily duties are diverse including everything from introducing music acts at local concerts to interviewing top stars.

— tara bradley connell, Orlando Signature, "Best-Dressed A-Listers in Orlando," 24 Aug. 2017
In that moment, Trump committed the gravest act of sacrilege of his presidency.

— jonathan haidt, The Atlantic, "Trump Breaks a Taboo—and Pays the Price," 21 Aug. 2017
The first time a person allows 14,000 gallons of water to fully support his or her body weight becomes an act of faith.

— matt grant, Longreads, "In a Swimming Pool, Learning to Trust," 21 Aug. 2017

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.

Origin and Etymology of act

Middle English, partly from Latin actus doing, act, from agere to drive, do; partly from Latin actum thing done, record, from neuter of actus, past participle of agere — more at agent

NEW! Time Traveler

First Known Use: 14th century

See Words from the same year

act Synonyms

Synonyms

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

Related Words

signature

Near Antonyms

bluntness, candidness, candor, directness, forthrightness, frankness, openheartedness, outspokenness, plainspokenness, sincerity, straightforwardness; artlessness, genuineness, naïveté (also naivete or naiveté)

act

verb

Definition of act

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

c :impersonate

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

play \ˌak-tə-ˈbi-lə-tē\ noun

—

actable

play \ˈak-tə-bəl\ adjective

See act defined for English-language learners

Examples of act in a Sentence

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.

Recent Examples of act from the Web

What's more, the federal plan that acts as homeowners' flood insurer of last resort is staggering under $25 billion in debt and is scheduled to expire in late September.

— robert reed, chicagotribune.com, "Pictures from Houston demonstrate need to fix the nation's flood insurance system," 30 Aug. 2017
But Truman acted only after South Korea—and American troops occupying it—had come under attack.

— garrett epps, The Atlantic, "Trump Doesn't Have the Authority to Attack North Korea Without Congress," 30 Aug. 2017
The restaurant owners at Mrs Winner’s called police when the pair began to act suspicious after a string of robberies at other fast-food restaurants. - At the time of the murders, Blakely was the youngest woman in Georgia to face the death penalty.

— ashley stoney, Essence.com, "Who Is The Real Falicia Blakely? Here Are Six Things To Know," 29 Aug. 2017
The yellowish serum in the middle contains agents that act to fight inflammation, and proteins to block pain, and it is injected back into the patient.

— larry stone, The Seattle Times, "Seahawks go all in on blood-spinning treatment, but does it really work?," 29 Aug. 2017
The center, along with the other two sites, will continue to act as cooling centers through Wednesday.

— andy nguyen, Glendale News-Press, "Cooling centers provide respite from heat wave in Glendale," 29 Aug. 2017
Despite his obvious talent as a footballer, his most serious altercation came in 2016 when he was handed a two-month prison sentence and fined for reportedly acting violently towards a police officer outside a Parisian nightclub.

— SI.com, "Report: Aurier Completes Tottenham Medical, Transfer Still Rests on Work Permit," 26 Aug. 2017
Before handing Busking a ceremonial oversized check, acting Lottery Director Greg Smith took the chance to plug the agency's marketing catchphrase.

— gregory pratt, Daily Southtown, "Retired Palos Heights woman claims $393 million jackpot: 'An out of body experience'," 25 Aug. 2017
Barca tried to walk a line, criticizing the process of quickly acting on the bill and saying that more improvements could be made to protect taxpayers, Wisconsin businesses and the environment.

— scott bauer, Milwaukee Journal Sentinel, "Democrat ‘incredibly frustrated’ with leader Barca over Foxconn," 21 Aug. 2017

Origin and Etymology of act

see ¹act

NEW! Time Traveler

First Known Use: 1590

See Words from the same year

act Synonyms

Synonyms

do, impersonate, interpret, perform, play, portray

Related Words

depict, dramatize, render, represent; act out, enact, pantomime, playact, role-play, take on; overact, overplay, underplay; ape, clown, ham, imitate, masquerade, mime, mimic, pose (as); star (in); coact, costar

Near Antonyms

backfire; fizzle

act

abbreviation

Definition of act

1 active

2 actor

3 actual

Other Performing Arts Terms

diva, dramaturgy, loge, prestidigitation, proscenium, supernumerary, zany

ACT

abbreviation

Definition of ACT

1 Action for Children's Television

2 Association of Classroom Teachers

3 Australian Capital Territory

See ACT defined for English-language learners

Other Education Terms

baccalaureate, colloquium, corequisite, dissertation, monograph, pedant, practicum, survey course, thesis

ACT

trademark \ ˌā-ˌsē-ˈtē \

Definition of ACT

—used for a standardized achievement test to evaluate suitability for college admission

Other Education Terms

baccalaureate, colloquium, corequisite, dissertation, monograph, pedant, practicum, survey course, thesis

ACT Defined for English Language Learners

act

noun

Definition of act for English Language Learners

: something that is done
: a law made by a group of legislators
: one of the main divisions of a play or opera

act

verb

Definition of act for English Language Learners

: to do something : to take action
: to behave in a particular way
: to behave in a way that is not sincere or honest

ACT Defined for Kids

act

noun \ ˈakt \

Definition of act for Students

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

Definition of act for Students

acted; acting

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

Medical Dictionary

act

noun \ ˈakt \

medical Definition of act

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

1 :to perform an act :behave

2 :to produce an effect

wait for a medicine to act

act

abbreviation

medical Definition of act

active

Law Dictionary

act

noun

legal Definition of act

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 act
—U.S. Code

b :a decision or determination of a sovereign, a legislative council, or a court of justice — compare bill 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

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 President
—U.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

play \ˈak-tər\ noun

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Examples of act in a Sentence

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Origin and Etymology of act

act Synonyms

Synonyms

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Near Antonyms

act

Definition of act

actability

actable

Examples of act in a Sentence

Recent Examples of act from the Web

Origin and Etymology of act

act Synonyms

Synonyms

Related Words

Near Antonyms

act

Definition of act

Other Performing Arts Terms

ACT

Definition of ACT

Other Education Terms

ACT

Definition of ACT

Other Education Terms

ACT Defined for English Language Learners

act

Definition of act for English Language Learners

act

Definition of act for English Language Learners

ACT Defined for Kids

act

Definition of act for Students

act

Definition of act for Students

Medical Dictionary

act

medical Definition of act

act

medical Definition of act

act

medical Definition of act

Law Dictionary

act

legal Definition of act

act

legal Definition of act

actor

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