Etymology From Middle English acte, from Old French acte, from Latin ācta (“register of events”), plural of āctum (“decree, law”), from agere (“to do, to act”), ultimately from Proto-Indo-European *h₂éǵeti. Compare German Akte (“file”). Partially displaced deed, from Old English dǣd (“act, deed”).
that we act our temporal affairs with a deſire no greater than our neceſſity1651, Jer[emy] Taylor, “Signes of Purity of Intention”, in The Rule and Exercises of Holy Living. […], 2nd edition, London: […] Francis Ashe […], →OCLC, page 23:
Industry doth beget by producing good habits, and facility of acting things expedient for us to do.a. 1678 (date written), Isaac Barrow, “(please specify the chapter name or sermon number)”, in The Works of Dr. Isaac Barrow. […], volume (please specify |volume=I to VII), London: A[braham] J[ohn] Valpy, […], published 1830–1831, →OCLC:
1 more example
Uplifted hands that at convenient times / Could act extortion and the worst of crimes.1782, William Cowper, Expostulation:
3
To perform a theatrical role.
I started acting at the age of eleven in my local theatre.
4
Of a play: to be acted out (well or badly).
But whatever types he assumes, the need to have a good play which acts delightfully well before the audience, and to their delectation, is the dominant thrust. If the play acts well, the director gets the credits.2011, Effiong Johnson, Play Production Processes, page 180:
5
To behave in a certain manner for an indefinite length of time.
A dog which acts aggressively is likely to bite.
I believe that Bill’s stuck-up because of the way that he acts.
1 more example
He’s acting strangely—I think there’s something wrong with him.
6
To convey an appearance of being.
He acted unconcerned so the others wouldn’t worry.
7
To do something that causes a change binding on the doer.
act on behalf of John
8
Construed with on or upon To have an effect (on).
High-pressure oxygen acts on the central nervous system and may cause convulsions or death.
Gravitational force acts on heavy bodies.
9
To play (a role).
He’s been acting Shakespearean leads since he was twelve.
10
To feign.
He acted the angry parent, but was secretly amused.
With acted fear the villain thus pursued.1697, Virgil, “The Second Book of the Æneis”, in John Dryden, transl., The Works of Virgil: Containing His Pastorals, Georgics, and Æneis. […], London: […] Jacob Tonson, […], →OCLC:
11
Law To carry out work as a legal representative in relation to a particular legal matter.
A lawyer cannot act until they have been formally instructed by their client.
12
Mathematics, SciencesConstrued with on or upon, Of an algebraic structure To possess an action onto (some other structure). Examples include the group action of a group on a set, the action of a ring on a module by scalar multiplication, and the action of a group or algebra on a vector space via a representation.
This group acts on the circle, so it can't be left-orderable!
13
Obsolete To move to action; to actuate; to animate.
Self-love, the spring of motion, acts the soul.1733, [Alexander Pope], An Essay on Man. […], (please specify |epistle=I to IV), London: […] J[ohn] Wilford, […], →OCLC:
Abbreviation, Ellipsis Ellipsis of Act of Parliament.
act
noun
Etymology From Middle English acte, from Old French acte, from Latin ācta (“register of events”), plural of āctum (“decree, law”), from agere (“to do, to act”), ultimately from Proto-Indo-European *h₂éǵeti. Compare German Akte (“file”). Partially displaced deed, from Old English dǣd (“act, deed”).
The seeds of plants are not at first in act, but in possibility, what they afterward grow to be.[1594], Richard Hooker, edited by J[ohn] S[penser], Of the Lawes of Ecclesiastical Politie, […], London: […] Iohn Windet, […], →OCLC, (please specify the page):
3
Lifestyle, Religion, Theology Something done once and for all, as distinguished from a work.
But was it responsible governance to pass the Longitude Act without other efforts to protect British seamen? Or might it have been subterfuge—a disingenuous attempt to shift attention away from the realities of their life at sea.2012 March 23, William E. Carter, Merri Sue Carter, “The British Longitude Act Reconsidered”, in American Scientist, volume 100, number 2, page 87:
5
Law (In the United States) A legislative proposal, a bill that has not yet become law.
Under current law, employers can drag out the union election process... Under the PRO Act, workers and the NLRB set union election procedures. The employer is not involved.2021 February 4, Celine McNicholas, Margaret Poydock, Lynn Rhinehart, “How the PRO Act restores workers' rights to unionize”, in Economic Policy Institute:
“H'm !” he said, “so, so—it is a tragedy in a prologue and three acts. I am going down this afternoon to see the curtain fall for the third time on what […] will prove a good burlesque ; but it all began dramatically enough. It was last Saturday […] that two boys, playing in the little spinney just outside Wembley Park Station, came across three large parcels done up in American cloth. […]”1904–1905, Baroness Orczy [i.e., Emma Orczy], “The Lisson Grove Mystery”, in The Case of Miss Elliott, London: T[homas] Fisher Unwin, published 1905, →OCLC; republished as popular edition, London: Greening & Co., 1909, OCLC 11192831, quoted in The Case of Miss Elliott (ebook no. 2000141h.html), Australia: Project Gutenberg of Australia, February 2020:
The pivotal moment in the play was in the first scene of the second act.
9
A performer or performers in a show.
Which act did you prefer? The soloist or the band?
10
Any organized activity.
The minute you let it be known you're planning a sales campaign everybody wants to get into the act.1934, Babette Hughes, One egg: a farce in one act, page 46:
11
A display of behaviour.
12
A display of behaviour meant to deceive.
to put on an act
He said, "I'm just curious, is this for real or just an act? / Can't tell if you love or hate me, never met someone like that"2023 September 15, Tate McRae, Amy Allen, Jasper Harris, Ryan Tedder, “Greedy”, in Think Later, performed by Tate McRae:
13
A thesis maintained in public, in some English universities, by a candidate for a degree, or to show the proficiency of a student.
14
LawAbbreviation, Ellipsis Ellipsis of act of parliament.