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
acted; acting; acts
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
1
a
: to represent or perform by action especially on the stage
will act the part of Romeo in tonight's play
c
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.
1
active
2
actor
3
actual
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
Synonyms
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
Katie Bain, Billboard, 11 Apr. 2024
The fest will also welcome acts from the United Kingdom including K-Trap and Unknown T, as well as worldwide musicians Money Boy, Gola Gianni, Ufo 361, Pashanim, Reezy, Shirin David, Rondodasosa and Fresh.
—Steven J. Horowitz, Variety, 11 Apr. 2024
Some of Israel’s supporters have been unwilling to acknowledge that IDF field troops and commanders have committed horrendous acts against civilians, whether due to indifference, recklessness, or vengefulness.
—Ahmed Fouad Alkhatib, The Atlantic, 10 Apr. 2024
The act of vandalism comes against a backdrop of rising anti-Muslim and anti-Arab bias incidents in the United States, according to CAIR.
—Celina Tebor, CNN, 10 Apr. 2024
The city has updated an ordinance — known as the city’s weed and vegetation enforcement act — that has guided gardeners on what plants are deemed noxious.
—Debra Skodack, Kansas City Star, 10 Apr. 2024
In recent days, defense lawyers for Trump and his adult sons have attempted to recast Weisselberg's guilty plea as an act of legal coercion, rather than an acknowledgement of wrongdoing.
—Aaron Katersky, ABC News, 10 Apr. 2024
With three stages located atop a wooded hillside in southeastern Louisville, additional acts playing at The Big Stomp include Ben Sollee, Saxsquatch, the Biblehauser Brothers, Doom Gong, White Whooly, Lacey Guthrie and more.
—Kirby Adams, The Courier-Journal, 9 Apr. 2024
Breakthrough star Megan Moroney also scored six nominations — the most for a female act.
—Mesfin Fekadu, The Hollywood Reporter, 9 Apr. 2024
Claire Peltier, ABC News, 12 Apr. 2024
However, Kathleen Zellner, Avery's defense attorney, has said that new evidence shows Dassey acted alone.
—Christina Coulter, Fox News, 12 Apr. 2024
There will be a machine there that the Secret Service said acts like a giant x-ray machine.
—Ricardo Torres, Journal Sentinel, 12 Apr. 2024
Read on to see our top bedding picks from Nate Home, but act fast to add them to your cart because inventory is moving fast.
—Clara McMahon, Peoplemag, 12 Apr. 2024
Thompson said he’s heard from many parents who have acted on the letters.
—Kavitha Cardoza, CNN, 12 Apr. 2024
The slowdown in electric vehicle sales continues to snowball, with plummeting resale values acting as another roadblock.
—Medora Lee, USA TODAY, 11 Apr. 2024
Tubulins make up tubular filaments known as microtubules, which act like cells’ skeletons.
—Will Sullivan, Smithsonian Magazine, 11 Apr. 2024
This announcement comes about a month after Meghan Markle subtly announced her mysterious new lifestyle brand American Riviera Orchard, which many believe will act as a Goopified version of her old blog, The Tig.
—Emily Tannenbaum, Glamour, 11 Apr. 2024
Noun
The album’s success validated the act — to an extent.
—Katie Bain, Billboard, 11 Apr. 2024
The fest will also welcome acts from the United Kingdom including K-Trap and Unknown T, as well as worldwide musicians Money Boy, Gola Gianni, Ufo 361, Pashanim, Reezy, Shirin David, Rondodasosa and Fresh.
—Steven J. Horowitz, Variety, 11 Apr. 2024
Some of Israel’s supporters have been unwilling to acknowledge that IDF field troops and commanders have committed horrendous acts against civilians, whether due to indifference, recklessness, or vengefulness.
—Ahmed Fouad Alkhatib, The Atlantic, 10 Apr. 2024
The act of vandalism comes against a backdrop of rising anti-Muslim and anti-Arab bias incidents in the United States, according to CAIR.
—Celina Tebor, CNN, 10 Apr. 2024
The city has updated an ordinance — known as the city’s weed and vegetation enforcement act — that has guided gardeners on what plants are deemed noxious.
—Debra Skodack, Kansas City Star, 10 Apr. 2024
In recent days, defense lawyers for Trump and his adult sons have attempted to recast Weisselberg's guilty plea as an act of legal coercion, rather than an acknowledgement of wrongdoing.
—Aaron Katersky, ABC News, 10 Apr. 2024
With three stages located atop a wooded hillside in southeastern Louisville, additional acts playing at The Big Stomp include Ben Sollee, Saxsquatch, the Biblehauser Brothers, Doom Gong, White Whooly, Lacey Guthrie and more.
—Kirby Adams, The Courier-Journal, 9 Apr. 2024
Breakthrough star Megan Moroney also scored six nominations — the most for a female act.
—Mesfin Fekadu, The Hollywood Reporter, 9 Apr. 2024
Verb
There are classes on acting from Steve Martin and Helen Mirren, on photography from Annie Leibovitz, on music from Ringo Starr, on science and technology from Neil deGrasse Tyson and James Cameron, to name a few.
—Claire Peltier, ABC News, 12 Apr. 2024
However, Kathleen Zellner, Avery's defense attorney, has said that new evidence shows Dassey acted alone.
—Christina Coulter, Fox News, 12 Apr. 2024
There will be a machine there that the Secret Service said acts like a giant x-ray machine.
—Ricardo Torres, Journal Sentinel, 12 Apr. 2024
Read on to see our top bedding picks from Nate Home, but act fast to add them to your cart because inventory is moving fast.
—Clara McMahon, Peoplemag, 12 Apr. 2024
Thompson said he’s heard from many parents who have acted on the letters.
—Kavitha Cardoza, CNN, 12 Apr. 2024
The slowdown in electric vehicle sales continues to snowball, with plummeting resale values acting as another roadblock.
—Medora Lee, USA TODAY, 11 Apr. 2024
Tubulins make up tubular filaments known as microtubules, which act like cells’ skeletons.
—Will Sullivan, Smithsonian Magazine, 11 Apr. 2024
This announcement comes about a month after Meghan Markle subtly announced her mysterious new lifestyle brand American Riviera Orchard, which many believe will act as a Goopified version of her old blog, The Tig.
—Emily Tannenbaum, Glamour, 11 Apr. 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
Phrases Containing act
Dictionary Entries Near act
Cite this Entry
“Act.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/act. Accessed 16 Apr. 2024.
Copy Citation
Kids Definition
act
1 of 2 noun1
: 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 verb1
: 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
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
Legal Definition
act
1 of 2 noun1
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
U.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 verb1
: 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
U.S. Constitution art. II3
: 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
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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