Act (pronounced akt)
(1) Anything done, being done, or to be done; deed;
performance.
(2) The process of doing.
(3) A formal decision, law, or the like, by a
legislature, ruler, court, or other authority; decree or edict; statute;
judgment, resolve, or award (with initial capital when part of a name). An act is created by a legislature passing a
bill.
(4) An instrument or document stating something done or
transacted.
(5) One of the main divisions of a play or opera.
(6) A short performance by one or more entertainers,
usually part of a variety show or radio or television program or the personnel
of such a group.
(7) A false show; pretence; feint.
(8) In scholasticism (a medieval school of 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 (an occurrence effected by the volition of a human agent, usually
opposed at least as regards its explanation to one which is causally determined).
(9) To do something; exert energy or force; be employed
or operative.
(10) To reach, make, or issue a decision on some matter.
(11) To operate or function in a particular way; perform
specific duties or functions.
(12) To produce an effect; perform a function; to behave
or conduct oneself in a particular fashion.
(13) To pretend; feign.
(14) to represent (a fictitious or historical character)
with one's person; to perform as an actor.
(15) To serve or substitute (usually followed by for).
(16) To actuate, to move to action; to actuate; to
animate (obsolete).
(17) As ACT, the initialization for Australian Capital
Territory, a federal territory created for the establishment of Canberra as
Australia’s capital city.
(18) In certain English universities, a thesis maintained
publicly by a candidate for a degree, or to show the proficiency of a student.
(19) In mathematics, construed with on or upon, of a
group; to map via a homomorphism to a group of automorphisms.
(20) In Scottish law, to enact, decree (obsolete).
(21) In slang, as "Dutch act", suicide.
1350–1400: From the Middle English act & acte, from the Old
French acte, from the Latin ācta (register of events), plural of āctum (decree, law (later “something
done”)), noun use of the past participle of agere
(to set in motion, drive, drive forward", hence "to do, perform"
and figuratively "incite to action; keep in movement, stir up" a verb
with a broad range of meaning in Latin, including "act on stage, play the
part of; plead a cause at law; chase; carry off, steal”), the construct being āg- (past participle stem) + -tum (the neuter past participle suffix)
and directly from the Latin āctus (a
doing; a driving, impulse, a setting in motion; a part in a play), the
construct being āg- + -tus (the suffix of verbal action); the
ultimate source was the primitive Indo-European héǵeti. The word partially displaced deed (which endured also
to enjoy a specific meaning in law), from the
Old English dǣd (act, deed). Source of it all was the primitive Indo-European root ag- (to drive, draw out or forth, move). Act is a noun, verb & adverb, acting is a noun, verb & adjective, active is a noun & adjective, actuation, actuator, activation, activity, acter, actor & actress are nouns, actuate, activating, acted & activate are verbs, acting is a noun, verb & adjective, activated is a verb & adjective, actuatable & actless are adjectives and actively is an adverb; the noun plural is acts.

“An act of God”: Last moments of the Hindenburg (Luftschiff Zeppelin #129; Registration: D-LZ 129), Manchester Township, New Jersey, United States, 6 May, 1937. The German dirigibles were hydrogen-filled because the US declined to supply helium to the Nazi regime (1933-1945). A chemically inert noble gas, helium is neither combustible nor flammable.
The theatrical (part of a play (from the 1510s)) and the
early fifteenth century legislative senses of the word existed also in Latin
although the idea of "one of a series of performances in a variety
show" seems not to have been in use until the 1890s although such forms of
entertainment were by then long-established.
The (usually disparaging) use to suggest a "display of exaggerated
behavior" is from 1928, extended from the theatrical sense. The "act of God” (a natural force or
event uncontrollable by man) was first recorded in 1726 as a legal term to
refer to matters in which plaintiffs could not sue for compensation or relief because
the consequent losses could not by anyone have been “…guarded against by the ordinary exertions of human skill and prudence
so as to prevent its effect.” Even
Adolf Hitler (who wasn't fond of of churches and priests (the Roman Catholic ones he called "black crows") found it often convenient to invoke the name of the Almighty) found the concept
helpful, describing the destruction of the Hindenburg dirigible in 1937 as “an act of God”. The word had been in the language of law for
a while, an act in the 1590s understood as something "in the process"
and legal scholars link this with the late sixteenth century use of act as a euphemism
for "sexual intercourse”.
The verb was a mid fifteenth century development from the
noun and most of the modern senses in English probably are from the noun. In the mid 1400s, it began with the sense of "to
act upon or adjudicate in legal matters” before from circa 1600 coming to be
used in the familiar general meaning of "to do, perform, transact", extended
to things in the sense of "do something, exert energy or force”, by 1751,
a use which would become increasingly common in physics and cosmology. In theatrical performances, from the 1590s it
meant to "perform as an actor" (intransitive) and by the 1610s "represent
by performance on the stage" (transitive). The meaning "perform
specific duties or functions," often on a temporary basis, had come into
use by 1804 and was given a new legitimacy when the Duke of Wellington (1769–1852;
UK prime-minister 1828-1830) was described as “acting prime-minister” between November-December
1834 while awaiting the return from Italy of the king’s appointee. One verb form which in general use didn’t
survive was "co-act" (to act together in a performance), noted from circa 1600, it begat co-action; co-active; co-actor etc although co-act (and
variations) is still sometimes used in scientific papers.

Hitler addressing the Reichstag (sitting in the Kroll Opera House after the Reichstag building was
torched) on the matter of the Enabling Act, Berlin, 23 March, 1933. Göring (who once claimed (latter denied) to have to have arranged the arson) is presiding as
President of the Reichstag (1932-1945).
In
legislation, the part played by the “act” differs between systems but, as a general
principle, the convention used in Westminster System parliaments in
illustrative of the process: A “bill” for an “act [of parliament]” is
introduced to the relevant chamber or parliament and if “passed” according to
due constitutional process, the act becomes “law”. One of history’s more notorious acts was the
German Enabling Act of 1933 (Gesetz zur
Behebung der Not von Volk und Reich (literally “Law to Remedy the Distress of People and Reich”), the legislative device
from which flowed the erosion of checks and balances in the Weimar-era (1918-1933)
constitution (that, remarkably, was never repealed and, in the narrow legal
sense, endured until the dissolution of the Nazi state in 1945), culminating in
Adolf Hitler (1889-1945; Führer (leader) and German head of government
1933-1945 & head of state 1934-1945) in 1943 gaining absolute, personal,
dictatorial power. Enabling acts (Ermächtigungsgesetz (in German, literally “empowering law”)) exist in many systems usually are merely procedural,
devices by which a legislature delegates some power(s) to an entity (or
individual) but what was notable about the Ermächtigungsgesetz of 23 March, 1933 was it provided the legal legitimacy for the Nazi’s
subsequent transformation of Germany into a totalitarian state; it became, in
effect, an absolute monarchy (albeit it a chaotic one, something not fully
appreciated until well after the end of hostilities in 1945). Because, structurally, the act was an amendment to the
Weimar constitution, a vote by a “super-majority” (essentially two-thirds of
members of the Reichstag (the German parliament)) was required and the Nazis at
that point “didn’t have the numbers”. However, to people like Hitler and Hermann
Göring (1893–1946; leading Nazi 1922-1945, Hitler's designated successor &
Reichsmarschall 1940-1945), that was little more than a tiresome irritant and
through the methods that had until then served them well (lies, threats, coercion, violence & bribery), duly the Reichstag passed the act.
To “act on” in the sense of "to exert influence upon"
entered general use in the 1810s, the adoption encouraged by the increasing appearance
of the phrase in scientific literature. To
“act up” came by 1900 mean "be unruly" (in reference to a horse in
the same way bolter (ie “to bolt” in the sense of “gallop off without warning”)) was used, a reversal of the earlier meaning "acting in accordance with a
duty, expectation, or belief” which dates from 1645. To “act out” (behave anti-socially) was part
of the jargon of psychiatry noted first in 1974; it meant "expressing
one's unconscious impulses or desires", following “acting out” (abnormal
behavior caused by unconscious influences) from 1945. The idiomatic forms are legion. “To get into the act” (participate) dates
from 1947 and “to get (one's) act together” (organize one's chaotic life) is
said not to have been used until the mid-1970s which seems surprising but more
than one source records this. The idea
of the “one-act” was borrowed from the literal “one act play” (a performance consisting
of a single act), noted since 1888, the figurative use suggesting either
brevity or inadequacy depending on context.
The verb overact (to go too far in action) faded from use except in its
original sense from the theatre where it described an actor “playing a part
with too much emphasis; an extravagant and unnatural manner”. The theatrical slang encapsulating this was “chewing
the scenery", which sounds modern but dates from the 1630s. To “act one’s age” is to behave in a manner befitting
the maturity one is presumed to have attained at a certain stage in life. An “act of faith” is to embark on a course of
action on either (1) a basis of trust rather than any guarantee or (2) as a demonstration
one's religious faith.
Acts & Scenes

The act is a major division in
many performance pieces such as plays, film, opera etc and frequently (though
not of necessity) consists of a number of scenes, the concept dating from the
theatre of antiquity. Traditionally, the
division of a work into acts and scenes was undertaken by the author but such delineations,
especially of older material, can be made by critics or those applying academic
analysis and where the notion of authorship can become blurred (such as a film
director interpreting a text), there can be variations from the original, something
sometimes controversial. The application
of the concept (and the labels) of acts and scenes is widely applied to many
forms of entertainment, sometimes to provide a structural framework and
sometimes, one suspects, to lend a not always deserved gravitas. In the production of more recent material,
commercial imperatives can also dictate the divisions, the single intermission
a common occurrence which renders a performance inherently a two-stage event in
some sense.

The five-act structure.
The number of acts in a piece need not bear any
relationship to its length although this certainly is the general tendency, a
one act play usually a deliberately short work.
Although the five act structure had until the early nineteenth century
been most frequently used by playwrights, many analysts suggest this was a kind
of formalism, a deferential (and perhaps devotional) nod to William Shakespeare
(circa 1564–1616) who usually adhered to the five act model in his plays. The bard had his reasons and there is a discernible
rhythm as his five acts evolve but none the less, even in the most intricate of
his plays, it’s possible convincingly to map onto them the now conventional
three act structure.

The three act structure.
The three-act structure can simply and unexceptionally be
understood as the beginning, middle and end. It's in act one the nature of the
conflict is established with the identities of protagonist and antagonist are
revealed (or in the case of the latter, at least alluded to. During the second act, difficulties will arise,
these the dramatic device used to create the insurmountable obstacle(s) likely to defeat the protagonist. In the
third act, there will be a climax (and perhaps an anti-climax or two), the point at
which all seems finally lost for the protagonist. However, despite it all, the protagonist
prevails and, even if they die, the circumstances will be such a resolution attained
is sufficient to satisfy the moral point being made.
F. Scott Fitzgerald with wife Zelda (Zelda Sayre,
1900-1948) in then fashionable fur.
F. Scott Fitzgerald’s (1896–1940) oft-quoted phrase “there are no second acts in American lives”
appears as a fragment in his posthumously published, unfinished novel The Last Tycoon (1941) but he first
published it in the early 1930s in the essay My Lost City, a kind of love letter to New York. The quote is frequently misunderstood as an
observation that for those Americans who suffer disgrace or destitution, there
is no redemption, no coming back. Comebacks in the US are of course frequent and some in politics have been remarkable. What Richard Nixon (1913-1994; VPOTUS 1953-1961 and POTUS 1969-1974) achieved in winning the presidency in 1968 was extraordinary and in matching that achievement in 2024, Donald Trump (b 1946; POTUS 2017-2021 and since 2025) managed what must in 2021 have seemed impossible. In the orthodoxy of conventional theatre, the final act is the third or fifth depending on the work's structure and this is followed also in idiomatic use. Benito
Mussolini (1883-1945; Duce (leader) & Prime-Minister of Italy 1922-1943) in
1938, gloomily contemplating the impending German annexation of neighboring Austria, told his foreign minister (Count Galeazzo Ciano (1903–1944; Italian
foreign minister 1936-1943 (and son-in-law of the Duce who ordered his
execution)): “We
find ourselves in the interval between the fourth and fifth acts of the Austrian
Affair.”

Second (third, fourth etc) act specialist: Lindsay Lohan
mug-shots 2007-2011.
However, from politics to pop culture, there are many
examples of temporarily disreputable Americans resurrecting their public lives from
all but the most ignominious opprobrium.
Fitzgerald was a professional writer and his observation was an allusion
to the structure used by playwrights in traditional three-act theatre: (1) problem,
(2) complication & (3) solution. He
thought the nature of the American mind was to prefer to skip the second act, going
straight from problem to resolution.
His point was well-made and it’s one of the themes of the narrative
which underlies the discussions (which became arguments and sometimes
squabbles) of military and political strategy between the high commands in Washington and London
during World War II (1939-1945). As early as 1942 the preferred strategy of General George Marshall (1880–1959; US Army chief of staff 1939-1945) was a triphibious invasion of France along the English Chanel coast as a staging post for a "march on Berlin", the operation to be staged either that year or the next. Like most of the senior ranks of the US military, he had little interest in the "secondary theatre" campaigns in Africa and the Mediterranean that so fascinated London; he wanted not to "nibble at the edges" but to go straight to the final act. Historians on both sides of the Atlantic have concluded to postpone the invasion to 1944 was strategically correct.