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RELATED WORDS

represent, play, give, show, offer, execute, produce, display, present, stage, exemplify, incarnate, manifest, typify, epitomize, embody, symbolize, illustrate, portray, imitate

Idioms

    act funny, to display eccentric or suspicious behavior.
    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.
    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.

Origin of act

1350–1400; Middle English act(e) (< Middle French) < Latin ācta, plural of āctum something done, noun use of past participle of agere to do (āg- past participle stem + -tum neuter past participle suffix); and directly < Latin āctus a doing (āg- + -tus suffix of v. action)
Related formsmis·act, verb (used without object)post·act, nounpre·act, verb (used with object)un·act·ed, adjectivewell-act·ed, adjective

Synonyms for act

SEE MORE SYNONYMS FOR act ON THESAURUS.COM
1. feat, exploit; achievement; transaction; accomplishment. See action. 4. record. 6. turn, routine. 10–13. perform, function, work. play. 19, 21 play.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for act out

act out

verb (adverb)

(tr) to reproduce (an idea, former event, etc) in actions, often by mime
psychiatry to express unconsciously (a repressed impulse or experience) in overt behaviour

ACT

1

abbreviation for

Australian Capital Territory
(formerly in Britain) advance corporation tax

ACT

2

n acronym for

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

act

noun

something done or performed; a deed
the performance of some physical or mental process; action
(capital when part of a name) the formally codified result of deliberation by a legislative body; a law, edict, decree, statute, etc
(often plural) a formal written record of transactions, proceedings, etc, as of a society, committee, or legislative body
a major division of a dramatic work
  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
an assumed attitude or pose, esp one intended to impress
philosophy an occurrence effected by the volition of a human agent, usually opposed at least as regards its explanation to one which is causally determinedCompare event (def. 4)

verb

(intr) to do something; carry out an action
(intr) to function in a specified way; operate; reacthis mind acted quickly
to perform (a part or role) in a play, etc
(tr) to present (a play, etc) on stage
(intr; usually foll by for or as) to be a substitute (for); function in place (of)
(intr foll by as) to serve the function or purpose (of)the glass acted as protection
(intr) to conduct oneself or behave (as if one were)she usually acts like a lady
(intr) to behave in an unnatural or affected way
(copula) to pose as; play the part ofto act the fool
(copula) to behave in a manner appropriate to (esp in the phrase act one's age)
(copula) not standard to seem or pretend to beto act tired
clean up one's act to start to behave in a responsible manner
get in on the act informal to become involved in a profitable undertaking or advantageous situation in order to share in the benefits
get one's act together informal to become organized or prepared
See also act on, act out, act up
Derived Formsactable, adjectiveactability, noun

Word Origin for act

C14: from Latin actus a doing, performance, and actum a thing done, from the past participle of agere to do
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for act out

act

v.

mid-15c., "to act upon or adjudicate" a legal case; 1590s in the theatrical sense, from Latin actus, past participle of agere (see act (n.)). To act up "be unruly" is from 1903. To act out "behave anti-socially" (1974) is from psychiatric sense of "expressing one's unconscious impulses or desires." Related: Acted; acting.

act

n.

late 14c., "a thing done," from Old French acte "(official) document," and directly from Latin actus "a doing, a driving, impulse; a part in a play, act," and actum "a thing done," originally a legal term, both from agere "to do, set in motion, drive, urge, chase, stir up," from PIE root *ag- "to drive, draw out or forth, move" (cf. Greek agein "to lead, guide, drive, carry off," agon "assembly, contest in the games," agogos "leader;" Sanskrit ajati "drives," ajirah "moving, active;" Old Norse aka "to drive;" Middle Irish ag "battle").

Theatrical ("part of a play," 1510s) and legislative (early 15c.) senses of the word also were in Latin. Meaning "display of exaggerated behavior" is from 1928. In the act "in the process" is from 1590s, perhaps originally from the 16c. sense of the act as "sexual intercourse." Act of God "uncontrollable natural force" recorded by 1726.

An act of God is an accident which arises from a cause which operates without interference or aid from man (1 Pars. on Cont. 635); the loss arising wherefrom cannot be guarded against by the ordinary exertions of human skill and prudence so as to prevent its effect. [William Wait, "General Principles of the Law," Albany, 1879]
Online Etymology Dictionary, © 2010 Douglas Harper
Idioms and Phrases with act out

act out

1

Perform or portray something or someone, as in As she read to the class, the teacher had each child act out a different character in the story. [c. 1600]

2

Express unconscious feelings or impulses through one's behavior, without being aware of it. For example, She acted out her anger at her father by screaming at her husband. This meaning comes from 20th-century psychological theory and usually (but not always) refers to negative or hostile impulses and emotions. The term is sometimes used without an object to mean “misbehave” or “behave disruptively,” as in The child is acting out in class. [First half of 1900s] In both usages, out means “openly” or “publicly.”

act

In addition to the idioms beginning with act

  • act of faith
  • act of God
  • act on
  • act one's age
  • act out
  • act up
  • act upon

also see:

  • 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
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.