act

[akt] /ækt/
noun
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.
  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)
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.
verb (used with object)
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.
Obsolete. to actuate.
Verb phrases
23.
act on/upon,
  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.
24.
act out,
  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.
25.
act up,
  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.
26.
get/have one's act together, Informal. to organize one's time, job, resources, etc., so as to function efficiently:
The new administration is still getting its act together.
Idioms
27.
act funny, to display eccentric or suspicious behavior.
28.
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.
29.
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
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 forms
misact, verb (used without object)
postact, noun
preact, verb (used with object)
unacted, adjective
well-acted, adjective
Can be confused
acts, ask, axe.
Synonyms
1. feat, exploit; achievement; transaction; accomplishment. See action. 4. record. 6. turn, routine. 23–13. perform, function, work. 15, 16. play.
British Dictionary definitions for act up

act up

verb
1.
(intransitive, adverb) (informal) to behave in a troublesome way: the engine began to act up when we were miles from anywhere

act

/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 pl) 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 (sense 4)
verb
9.
(intransitive) to do something; carry out an action
10.
(intransitive) to function in a specified way; operate; react: his mind acted quickly
11.
to perform (a part or role) in a play, etc
12.
(transitive) to present (a play, etc) on stage
13.
(intransitive; usually foll by for or as) to be a substitute (for); function in place (of)
14.
(intransitive) foll by as. to serve the function or purpose (of): the glass acted as protection
15.
(intransitive) to conduct oneself or behave (as if one were): she usually acts like a lady
16.
(intransitive) to behave in an unnatural or affected way
17.
(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 manner
21.
(informal) get in on the act, to become involved in a profitable undertaking or advantageous situation in order to share in the benefits
22.
(informal) get one's act together, to become organized or prepared
See also act on, act out, act up
Derived Forms
actable, adjective
actability, noun
Word Origin
C14: from Latin actus a doing, performance, and actum a thing done, from the past participle of agere to do

ACT1

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

ACT2

/ækt/
noun acronym
1.
(in New Zealand) Association of Consumers and Taxpayers: a small political party of the right
Word Origin and History for act up

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]

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.

Slang definitions & phrases for act up

act up

verb phrase

To misbehave badly or improperly, esp to impress: Her kids act up all the time (1900+)


act

noun
  1. A display of pretended feeling; an affected pretense: His elaborate grief was just an act
  2. A dramatic mimicking; shtick,takeoff: You oughta see my Brando act
Related Terms

a class act, clean up one's act, do the dutch, go into one's act, sister act


Related Abbreviations for act up

ACT

  1. a trademark for a standardized college entrance examination; originally American College Test
  2. American Conservatory Theater
  3. Waco Regional Airport
Idioms and Phrases with act up

act up

.
Misbehave. For example, With an inexperienced rider, this horse always acts up. [ c. 1900 ]
.
Malfunction, as in I'm not sure what's wrong with my car, but the transmission is acting up. In both usages up means “abnormally.”

act

also see: