act

¹

[ akt ]

noun

1. anything done, being done, or to be done; deed; performance:

   a heroic act.

   Synonyms: accomplishment, transaction, achievement, exploit, feat

2. the process of doing:

   caught in the act.

3. a formal decision, law, or the like, by a legislature, ruler, court, or other authority; decree or edict; statute; judgment, resolve, or award:

   an act of Congress.

4. an instrument or document stating something done or transacted.

   Synonyms: record

5. one of the main divisions of a play or opera:

   the second act of Hamlet.

6. a short performance by one or more entertainers, usually part of a variety show or radio or television program.

   Synonyms: routine, turn

7. the personnel of such a group:

   The act broke up after 30 years.

8. false show; pretense; feint:

   The politician's pious remarks were all an act.

9. Philosophy. (in scholasticism)
   1. activity in process; operation.
   2. the principle or power of operation.
   3. form as determining essence.
   4. a state of realization, as opposed to potentiality.

verb (used without object)

1. to do something; exert energy or force; be employed or operative:

   He acted promptly in the emergency.

   Synonyms: play, work, function, perform

2. to reach, make, or issue a decision on some matter:

   I am required to act before noon tomorrow.

   Synonyms: play, work, function, perform

3. to operate or function in a particular way; perform specific duties or functions:

   to act as manager.

   Synonyms: play, work, function, perform

4. to produce an effect; perform a function:

   The medicine failed to act.

   Synonyms: play, work, function, perform

5. to behave or conduct oneself in a particular fashion:

   to act well under all conditions.

6. to pretend; feign:

   Act interested even if you're bored.

7. to perform as an actor:

   He acted in three plays by Molière.

8. to be capable of being performed:

   His plays don't act well.

9. to serve or substitute (usually followed by for ):

   In my absence the assistant manager will act for me.

verb (used with object)

1. to represent (a fictitious or historical character) with one's person:

   to act Macbeth.

   Synonyms: play

2. to feign; counterfeit:

   to act outraged virtue.

3. to behave as:

   He acted the fool.

   Synonyms: play

4. Obsolete. to actuate.

verb phrase

1. 1. to fail to function properly; malfunction:

      The vacuum cleaner is acting up again.

   2. to behave willfully:

      The children always act up in school the day before a holiday.

   3. to become painful or troublesome, especially after a period of improvement or remission:

      My arthritis is acting up again this morning.

2. Informal. to organize one's time, job, resources, etc., so as to function efficiently:

   The new administration is still getting its act together.

3. 1. to act in accordance with; follow:

      He acted on my advice.

   2. to have an effect on; affect:

      The stirring music acted on the emotions of the audience.

4. 1. to demonstrate or illustrate by pantomime or by words and gestures:

      The party guests acted out stories for one another.

   2. Psychology. to give overt expression to (repressed emotions or impulses) without insightful understanding:

      The patients acted out early traumas by getting angry with the analyst.

ACT

²

1. Trademark. a standardized college admissions test developed by ACT, Inc., measuring English, mathematics, reading, and science skills: originally an abbreviation of American College Testing/American College Test. Compare SAT.
2. Association of Classroom Teachers.
3. Australian Capital Territory.

act.

³

abbreviation for

1. acting.
2. active.
3. actor.
4. actual.

ACT

¹

abbreviation for

1. Australian Capital Territory
2. (formerly in Britain) advance corporation tax

act

²

/ ækt /

noun

1. something done or performed; a deed
2. the performance of some physical or mental process; action
3. capital when part of a name the formally codified result of deliberation by a legislative body; a law, edict, decree, statute, etc
4. often plural a formal written record of transactions, proceedings, etc, as of a society, committee, or legislative body
5. a major division of a dramatic work
6. 1. a short performance of skill, a comic sketch, dance, etc, esp one that is part of a programme of light entertainment
   2. those giving such a performance
7. an assumed attitude or pose, esp one intended to impress
8. philosophy an occurrence effected by the volition of a human agent, usually opposed at least as regards its explanation to one which is causally determined Compare event

verb

1. intr to do something; carry out an action
2. intr to function in a specified way; operate; react

   his mind acted quickly

3. to perform (a part or role) in a play, etc
4. tr to present (a play, etc) on stage
5. intr; usually foll by for or as to be a substitute (for); function in place (of)
6. intrfoll byas to serve the function or purpose (of)

   the glass acted as protection

7. intr to conduct oneself or behave (as if one were)

   she usually acts like a lady

8. intr to behave in an unnatural or affected way
9. copula to pose as; play the part of

   to act the fool

10. copula to behave in a manner appropriate to (esp in the phrase act one's age )
11. not_standard.
    copula to seem or pretend to be

    to act tired

12. clean up one's act
    to start to behave in a responsible manner
13. get in on the act informal.
    to become involved in a profitable undertaking or advantageous situation in order to share in the benefits
14. get one's act together informal.
    to become organized or prepared

ACT

³

/ ækt /

acronym for

1. (in New Zealand) Association of Consumers and Taxpayers: a small political party of the right

Derived Forms

• ˈactable, adjective
• ˌactaˈbility, noun

Other Words From

• mis·act verb (used without object)
• postact noun
• pre·act verb (used with object)
• un·acted adjective
• well-acted adjective

Word History and Origins

Origin of act¹

First recorded in 1350–1400; Middle English act(e), from Middle French, from Latin ācta, plural of āctum “something done,” noun use of neuter past participle of agere “to do, drive”; also from Latin āctus “deed,” noun use of masculine past participle of agere

Word History and Origins

Origin of act¹

C14: from Latin actus a doing, performance, and actum a thing done, from the past participle of agere to do

Idioms and Phrases

Idioms

1. act funny, to display eccentric or suspicious behavior.
2. act one's age, to behave in a manner appropriate to one's maturity:

   We children enjoyed our uncle because he didn't always act his age.

3. clean up one's act, Informal. to begin adhering to more acceptable practices, rules of behavior, etc.:

   The factory must clean up its act and treat its employees better.

More idioms and phrases containing act

• catch in the act
• clean up (one's act)
• do a disappearing act
• get in the act
• get one's act together
• hard (tough) act to follow
• high-wire act
• in the act of
• put on an act

Synonym Study

See action.

Example Sentences

"But evolution acts on all parts of the body, great and small. Structures and regions that have been ignored are often gold mines for new insights and untold tales."

From Science Daily

The researchers engineered yeast to act as single-celled drug factories and produce immune checkpoint inhibitors -- anticancer drugs that alert immune cells to the presence of cancer cells.

From Science Daily

These groups act like switches, turning genes on or off or adjusting how strongly they are expressed.

From Science Daily

Currently held up in the Senate, the bill came to Trump's attention after a segment on the act aired on "PBS NewsHour."

From Salon

Laub has shown some remorse for her acts and, in a text thread uncovered by government agents, told a family member “I know what I did is unforgivable,” prosecutors said.

From Los Angeles Times

Related Words

• action
• deed
• move
• operation
• performance
• step
• thing