ACT 1 (??s?-t??) A trademark for a standardized college entrance examination.ACT 2abbr. Australian Capital Territoryact (?kt)n.1. The process of doing or performing something: the act of thinking.2. a. Something done or performed; a deed: a charitable act.b. Law Something done that has legal significance: a criminal act.3. A statute or other law formally adopted by a legislative body: an act of Congress.4. A formal written record of proceedings or transactions.5. One of the major divisions of a play, opera, or film.6. a. A performance or entertainment usually forming part of a longer presentation: a juggling act; a magic act.b. The actor or actors presenting such a performance: joined the act in Phoenix.7. A manifestation of intentional or unintentional insincerity; a pose: put on an act.v. act·ed, act·ing, acts v.tr.1. To play the part of; assume the dramatic role of: She plans to act Ophelia in summer stock.2. To perform (a role) on the stage: act the part of the villain.3. a. To behave like or pose as; impersonate: Don’t act the fool.b. To behave in a manner suitable for: Act your age.v.intr.1. To behave or comport oneself: She acts like a born leader.2. To perform in a dramatic role or roles.3. To be suitable for theatrical performance: This scene acts well.4. To behave affectedly or unnaturally; pretend.5. To appear or seem to be: The dog acted ferocious.6. To carry out an action: We acted immediately. The governor has not yet acted on the bill.7. To operate or function in a specific way: His mind acts quickly.8. To serve or function as a substitute for another: A coin can act as a screwdriver.9. To produce an effect: waited five minutes for the anesthetic to act.Phrasal Verbs: act out1. To perform in or as if in a play; represent dramatically: act out a story.2. To realize in action: wanted to act out his theory.3. To engage in socially inappropriate or impulsive behavior as a manifestation of psychological or emotional pain or turmoil. act up1. To misbehave.2. To malfunction.3. Informal To become active or troublesome after a period of quiescence: My left knee acts up in damp weather. Her arthritis is acting up again.Idioms: be in on the act To be included in an activity. clean up (one’s) act Slang To improve one’s behavior or performance. get into the act To insert oneself into an ongoing activity, project, or situation. get (one’s) act together Slang To get organized.[Middle English, from Old French acte, from Latin ?ctus, a doing, and ?ctum, a thing done, both from past participle of agere, to drive, do; see ag- in Indo-European roots.]ac?ta·bil?i·ty n.act?a·ble adj.Usage Note: Act and action both mean “a deed” and “the process of doing.” However, other senses of act, such as “a decision made by a legislative body” and of action, such as “habitual or vigorous activity” show that act tends to refer to a deed while action tends to refer to the process of doing. Thus, people engage in sex acts but not sex actions. By the same token, one may want a piece of the action, but not a piece of the act. The demands of meaning or idiom often require one word or the other. In some cases, either can be used: my act (or action) was premature.American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.act (ækt) n1. something done or performed; a deed2. the performance of some physical or mental process; action3. (Law) (capital when part of a name) the formally codified result of deliberation by a legislative body; a law, edict, decree, statute, etc4. (Law) (often plural) a formal written record of transactions, proceedings, etc, as of a society, committee, or legislative body5. (Theatre) a major division of a dramatic work6. (Theatre) a. a short performance of skill, a comic sketch, dance, etc, esp one that is part of a programme of light entertainmentb. those giving such a performance7. an assumed attitude or pose, esp one intended to impress8. (Philosophy) 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 event4vb9. (intr) to do something; carry out an action10. (intr) to function in a specified way; operate; react: his mind acted quickly. 11. (Theatre) to perform (a part or role) in a play, etc12. (Theatre) (tr) to present (a play, etc) on stage13. (intr; usually foll by for or as) to be a substitute (for); function in place (of)14. (foll by: as) to serve the function or purpose (of): the glass acted as protection. 15. (intr) to conduct oneself or behave (as if one were): she usually acts like a lady. 16. (intr) to behave in an unnatural or affected way17. (copula) to pose as; play the part of: to act the fool. 18. (copula) to behave in a manner appropriate to (esp in the phrase act one’s age)19. (copula) not standard to seem or pretend to be: to act tired. 20. clean up one’s act to start to behave in a responsible manner21. get in on the act informal to become involved in a profitable undertaking or advantageous situation in order to share in the benefits22. get one’s act together informal to become organized or prepared[C14: from Latin actus a doing, performance, and actum a thing done, from the past participle of agere to do] ?actable adj ?acta?bility nACT abbreviation for 1. (Placename) Australian Capital Territory 2. (Accounting & Book-keeping) (formerly in Britain) advance corporation tax ACT (ækt) n acronym for (Government, Politics & Diplomacy) (in New Zealand) Association of Consumers and Taxpayers: a small political party of the rightCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014act (ækt) n. 1. anything done, being done, or to be done; deed: an act of mercy. 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: 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. 6. a. a short performance by one or more entertainers, usu. part of a variety show, circus, etc. b. the routine or style by which an entertainer or group of entertainers is known: a magic act. c. the personnel of such a group. 7. a display of insincere behavior assumed for effect; pretense. v.i. 8. to do something; carry out an action; exert energy or force. 9. to reach or issue a decision on some matter. 10. to operate or function in a particular way: to act as manager. 11. to produce an effect: The medicine failed to act. 12. to behave or conduct oneself in a particular fashion. 13. to pretend; feign. 14. to perform as an actor. 15. to be capable of being performed: His plays don’t act well. v.t. 16. to represent (a fictitious or historical character) with one’s person: to act Macbeth. 17. to feign; counterfeit: to act outraged virtue. 18. to behave as: to act the fool. 19. to behave in a manner appropriate to: to act one’s age. 20. Obs. to actuate. 21. act for, to represent, esp. legally. 22. act on or upon, a. to act in accordance with; follow. b. to have an effect on; affect. 23. act out, a. to illustrate by pantomime or other gestures. b. to express (repressed emotions) inappropriately and without conscious understanding. 24. act up, a. to fail to function properly; malfunction. b. to behave willfully. c. (of a recurring ailment) to become painful or troublesome again. Idioms: 1. clean up one’s act, Informal. to begin adhering to more acceptable rules of behavior. 2. get or have one’s act together,Informal. to behave or function responsibly and efficiently. [1350?1400; Middle English (