anything done, being done, or to be done; deed; performance:
a heroic act.
the process of doing:
caught in the act.
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.
an instrument or document stating something done or transacted.
one of the main divisions of a play or opera: the second act of Hamlet.
a short performance by one or more entertainers, usually part of a variety show or radio or television program.
the personnel of such a group:
The act broke up after 30 years.
false show; pretense; feint:
The politician’s pious remarks were all an act.
activity in process; operation.
the principle or power of operation.
form as determining essence.
a state of realization, as opposed to potentiality.
to do something; exert energy or force; be employed or operative:
He acted promptly in the emergency.
to reach, make, or issue a decision on some matter:
I am required to act before noon tomorrow.
to operate or function in a particular way; perform specific duties or functions:
to act as manager.
to produce an effect; perform a function:
The medicine failed to act.
to behave or conduct oneself in a particular fashion:
to act well under all conditions.
to pretend; feign:
Act interested even if you’re bored.
to perform as an :
He acted in three plays by Molière.
to be capable of being performed:
His plays don’t act well.
to serve or substitute (usually followed by for):
In my absence the assistant manager will act for me.
to represent (a fictitious or historical character) with one’s person:
to act Macbeth.
to feign; counterfeit:
to act outraged virtue.
to behave as:
He acted the fool.
Obsolete. to .
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.
to demonstrate or illustrate by pantomime or by words and gestures:
The party guests acted out stories for one another.
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.
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.
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.
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.
Until that lesson is fully absorbed and acted upon, the conflict will surely drag on.
For Israelis and Arabs, A Time to Look Back—and Look Forward Alan Elsner September 11, 2013
Imagine if these early indications of a shift in culture were to be acted upon.
Sororities Finally Take Back the Night Kelsey Meany September 11, 2014
They acted upon the recommendation of the Judicial Conference that oversees U.S. judges.
Obama Picks Pawns in Political Fight as GOP Aims to Cut Down D.C. Circuit Court Eleanor Clift June 4, 2013
Commanders have also threatened to attack shops that stock her book, “I am Malala”—although it has not acted upon them.
Malala Book Launch Halted In Pakistan January 28, 2014
My story was hardly one the Rue de Jérusalem would have acted upon; and, besides, I wanted no interference.
A Stable for Nightmares J. Sheridan Le Fanu
No sooner did the thought occur to him than he acted upon it.
Brave and Bold Horatio Alger
It is true that a man is permitted to exercise it in his testamentary dispositions, but it is scarcely ever acted upon.
Early Western Travels, 1748-1846, Volume XII William Faux
In an instant I had decided my course; in an hour I had acted upon it.
The First Violin Jessie Fothergill
They acted upon the impulse of the moment, and I judged that at least one half of them were engaged in the demonstration.
Breaking Away Oliver Optic
The official had acted upon a secret idea in placing these papers before her.
The Fat and the Thin Emile Zola
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 pl) a formal written record of transactions, proceedings, etc, as of a society, committee, or legislative body
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
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 determined Compare event (sense 4)
(intransitive) to do something; carry out an action
(intransitive) to function in a specified way; operate; react: his mind acted quickly
to perform (a part or role) in a play, etc
(transitive) to present (a play, etc) on stage
(intransitive; usually foll by for or as) to be a substitute (for); function in place (of)
(intransitive) foll by as. to serve the function or purpose (of): the glass acted as protection
(intransitive) to conduct oneself or behave (as if one were): she usually acts like a lady
(intransitive) to behave in an unnatural or affected way
(copula) to pose as; play the part of: to 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 be: to act tired
clean up one’s act, to start to behave in a responsible manner
(informal) get in on the act, to become involved in a profitable undertaking or advantageous situation in order to share in the benefits
(informal) get one’s act together, to become organized or prepared
Australian Capital Territory
(formerly in Britain) advance corporation tax
(in New Zealand) Association of Consumers and Taxpayers: a small political party of the right
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]
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.
A display of pretended feeling; an affected pretense: His elaborate grief was just an act
A dramatic mimicking; shtick,takeoff: You oughta see my Brando act
a class act, clean up one’s act, do the dutch, go into one’s act, sister act
a trademark for a standardized college entrance examination; originally American College Test
American Conservatory Theater
Waco Regional Airport
act of faith
act of God
act one’s age
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
in the act of
put on an act
. abbreviation acting acting
Biochemistry. a polypeptide hormone, produced by the anterior lobe of the pituitary gland, that stimulates the cortex of adrenal glands. Pharmacology. this substance, extracted from the pituitary glands of hogs and other species, in the form of its white, water-soluble powder, used for the diagnosis of diseases that impair the adrenal glands. noun adrenocorticotrophic hormone; […]
- Acth-producing adenoma
acth-producing adenoma ACTH-producing adenoma n. A pituitary tumor causing Cushing’s syndrome, composed of basophilic, densely granulated corticotrophs. Also called basophil adenoma.
a promontory in NW ancient Greece: Antony and Cleopatra were defeated by Octavian and Agrippa in a naval battle near here in 31 b.c. Historical Examples The galleys “rammed” each other at Actium; but there was no Dahlgren or Sawyer to thunder from their decks or turrets. The Atlantic Monthly, Volume 15, No. 91, May, […]
- Actin filament
actin filament actin filament n. One of the contractile elements in skeletal, cardiac, and smooth muscle fibers.