1. anything done, being done, or to be done; deed; performance: a heroic act.
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.
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.
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)
• activity in process; operation.
• the principle or power of operation.
• form as determining essence.
• a state of realization, as opposed to potentiality.

10. to do something; exert energy or force; be employed or operative: He acted promptly in the emergency.
11. to reach, make, or issue a decision on some matter: I am required to act before noon tomorrow.
12. to operate or function in a particular way; perform specific duties or functions: to act as manager.
13. to produce an effect; perform a function: The medicine failed to act.
14. to behave or conduct oneself in a particular fashion: to act well under all conditions.
15. to pretend; feign: Act interested even if you're bored.
16. to perform as an actor: He acted in three plays by Molière.
17. to be capable of being performed: His plays don't act well.
18. to serve or substitute (usually followed by for): In my absence the assistant manager will act for me.

19. to represent (a fictitious or historical character) with one's person: to act Macbeth.
20. to feign; counterfeit: to act outraged virtue.
21. to behave as: He acted the fool.
22. to actuate.

23. act on / upon
• to act in accordance with; follow: He acted on my advice.
• to have an effect on; affect: The stirring music acted on the emotions of the audience.
24. act out,
• to demonstrate or illustrate by pantomime or by words and gestures: The party guests acted out stories for one another.
• to give overt expression to (repressed emotions or impulses) without insightful understanding: The patients acted out early traumas by getting angry with the analyst.
25. act up,
• to fail to function properly; malfunction: The vacuum cleaner is acting up again.
• to behave willfully: The children always act up in school the day before a holiday.
• to become painful or troublesome, especially after a period of improvement or remission: My arthritis is acting up again this morning.
26. to organize one's time, job, resources, etc., so as to function efficiently: The new administration is still getting its act together.

27. to display eccentric or suspicious behavior.
28. to behave in a manner appropriate to one's maturity: We children enjoyed our uncle because he didn't always act his age.
29. to begin adhering to more acceptable practices, rules of behavior, etc.: The factory must clean up its act and treat its employees better.

1. 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.
2. Association of Classroom Teachers.
3. Australian Capital Territory.

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

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

9. to do something; carry out an action
10. to function in a specified way; operate; react
11. to perform (a part or role) in a play, etc
12. to present (a play, etc) on stage
13. to be a substitute (for); function in place (of)
14. to serve the function or purpose (of)
15. to conduct oneself or behave (as if one were)
16. to behave in an unnatural or affected way
17. to pose as; play the part of
18. to behave in a manner appropriate to (esp in the phrase act one's age)
19. to seem or pretend to be
20. to start to behave in a responsible manner
21. to become involved in a profitable undertaking or advantageous situation in order to share in the benefits
22. to become organized or prepared

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

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

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