1

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

Examples of act in a Sentence

  1. We were grateful for her many acts of kindness.

  2. the Civil Rights Act of 1964

  3. Please read act II, scene 1 of Shakespeare's Romeo and Juliet.

  4. In the first act, two characters are talking in a restaurant.

Recent Examples of act from the Web

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


2

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
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

Examples of act in a Sentence

  1. He knew he had to act quickly.

  2. The government was slow to act.

  3. She acted on behalf of her father, who was not at the meeting.

  4. I believe that the killer acted alone.

  5. She had acted in self-defense when she killed her attacker.

  6. We were acting in the best interests of our children.

  7. We must act soon to end this crisis.

  8. She learned at an early age how to act properly in social situations.

  9. People are always telling me how I should act and what I should say.

  10. I noticed that the dog was acting funny this morning.

Recent Examples of act from the Web

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

see 1act


3

act

abbreviation

Definition of act

1 active
2 actor
3 actual

Other Performing Arts Terms


1

ACT

abbreviation

Definition of ACT

1 Action for Children's Television
2 Association of Classroom Teachers
3 Australian Capital Territory

2

ACT

trademark \ ˌā-ˌsē-ˈtē \

Definition of ACT

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

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

1

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.

2

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

1

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)

2

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

1

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

2

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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