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.
Recent Examples on the Web
Noun
The Grammy award-winning rapper will have several artists accompanying him along the way, but his Ohio audiences will be the only crowds getting four supporting acts: Pusha T, Earthgang, Cleveland native Chelsea Pastel and Siena Bella. Grace Tucker, The Enquirer, 6 Mar. 2024 Although the law does not specifically name the Confederate flag, many critics have noted that it would be protected under the act. Chandelis Duster, CNN, 6 Mar. 2024 The act imposes a 1% tax on incomes in excess of $1 million to fund the expansion of mental health treatment options in California, which will be redirected under Proposition 1. Taryn Luna, Los Angeles Times, 6 Mar. 2024 The War and Treaty, Jason Isbell and the 400 Unit, Sheryl Crow, and Sierra Ferrell are among the opening acts over the course of the trek. Daniel Kreps, Rolling Stone, 6 Mar. 2024 According to the act, time zones nor the amount of daylight hours would be altered. Brianna Taylor, Sacramento Bee, 6 Mar. 2024 The couple have performed frequently as a concert double act around San Diego. Pam Kragen, San Diego Union-Tribune, 5 Mar. 2024 According to local media, in January politician Regina Ip Lau Suk-yee asked Kevin Yeung Yun-hung (the secretary for culture, sports, and tourism) why more wasn’t being done to ensure acts like Swift visit the region. Eleanor Pringle, Fortune, 5 Mar. 2024 Yet this act of cynicism was also, perhaps, a political gift to Biden. Evan Osnos, The New Yorker, 4 Mar. 2024
Verb
Young Talent Big Dreams Competition: Kids in Miami-Dade County with music, acting, or performing talents can showcase their skills and potentially win big prizes by participating in the Young Talent Big Dreams competition, sponsored by The Trust and Actors’ Playhouse. Juliette Fabien, Miami Herald, 7 Mar. 2024 Beltrán’s influence extended beyond music to acting, earning her widespread acclaim and a star on the Hollywood Walk of Fame. Isabela Raygoza, Billboard, 7 Mar. 2024 Prosecutors argued Gutierrez Reed repeatedly violated safety protocol and acted negligently in performing her duties, and that her actions ultimately led to Hutchins’ death. Aj Willingham, CNN, 7 Mar. 2024 Collectively, the Fox brothers — my father’s relatives — wrote 50 films, directed 153, produced 33, acted in 37 and assisted in directing 14. Erik Himmelsbach-Weinstein, Los Angeles Times, 7 Mar. 2024 The top acting and directing nominees at the 96th Academy Awards are in for a treat. Demetrius Simms, Robb Report, 7 Mar. 2024 With eight Emmy noms and three wins (all for Maya Rudolph's voice acting), much of the world seems to agree. Debby Wolfinsohn, EW.com, 6 Mar. 2024 To take advantage of the deals, travelers will have to act fast as the sale ends at 11:59pm EST on Wednesday. Michael Cappetta, Travel + Leisure, 6 Mar. 2024 This represents to me a full circle of dedication to a craft (acting, in this case), grasping at the highest moment and then restarting the process again. Michael Slenske, The Hollywood Reporter, 6 Mar. 2024

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 19 Mar. 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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