verb (1)
af·​fect | \ ə-ˈfekt How to pronounce affect (audio) , a- \
affected; affecting; affects

Definition of affect

 (Entry 1 of 3)

transitive verb

: to produce an effect upon: such as
a : to produce a material influence upon or alteration in Paralysis affected his limbs.
b : to act upon (a person, a person's mind or feelings, etc.) so as to effect a response : influence We were all greatly affected by the terrible news.


af·​fect | \ ˈa-ˌfekt How to pronounce affect (audio) \

Definition of affect (Entry 2 of 3)

1 [German Affekt, borrowed from Latin affectus] : the conscious subjective aspect of an emotion considered apart from bodily changes also : a set of observable manifestations of a subjectively experienced emotion … patients … showed perfectly normal reactions and affects— Oliver Sacks
2 obsolete : feeling, affection


verb (2)
af·​fect | \ ə-ˈfekt How to pronounce affect (audio) , a- \
affected; affecting; affects

Definition of affect (Entry 3 of 3)

transitive verb

1 : to put on a pretense of : feign affect indifference, though deeply hurt He affected a French accent.
2 : to make a display of liking or using : cultivate affect a worldly manner
3a : to be given to : fancy affect flashy clothes
b archaic : to have affection for
4 : to tend toward drops of water affect roundness
6 archaic : to aim at

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Other Words from affect

Verb (1)

affectability \ ə-​ˌfek-​tə-​ˈbi-​lə-​tē How to pronounce affectability (audio) , a-​ \ noun
affectable \ ə-​ˈfek-​tə-​bəl How to pronounce affectable (audio) , a-​ \ adjective

Choose the Right Synonym for affect

Verb (1)

affect, influence, touch, impress, strike, sway mean to produce or have an effect upon. affect implies the action of a stimulus that can produce a response or reaction. the sight affected her to tears influence implies a force that brings about a change (as in nature or behavior). our beliefs are influenced by our upbringing touch may carry a vivid suggestion of close contact and may connote stirring, arousing, or harming. plants touched by frost his emotions were touched by her distress impress stresses the depth and persistence of the effect. only one of the plans impressed him strike, similar to but weaker than impress, may convey the notion of sudden sharp perception or appreciation. struck by the solemnity of the occasion sway implies the acting of influences that are not resisted or are irresistible, with resulting change in character or course of action. politicians who are swayed by popular opinion

Verb (2)

assume, affect, pretend, simulate, feign, counterfeit, sham mean to put on a false or deceptive appearance. assume often implies a justifiable motive rather than an intent to deceive. assumed an air of cheerfulness around the patients affect implies making a false show of possessing, using, or feeling. affected an interest in art pretend implies an overt and sustained false appearance. pretended that nothing had happened simulate suggests a close imitation of the appearance of something. cosmetics that simulate a suntan feign implies more artful invention than pretend, less specific mimicry than simulate. feigned sickness counterfeit implies achieving the highest degree of verisimilitude of any of these words. an actor counterfeiting drunkenness sham implies an obvious falseness that fools only the gullible. shammed a most unconvincing limp

Frequently Asked Questions About affect

What is the difference between affect and effect?

Both affect and effect can function as a noun or a verb. However, affect is most often found as a verb (“to produce an influence upon or alteration in”), and effect as a noun ("a change that results when something is done or happens”). For example, we can say that something that affects a person has an effect on them.

What is the difference between affection and affectation?

The more familiar word, affection, in modern use most often means "a feeling of liking and caring for someone or something." Affectation may be defined as "speech or conduct not natural to oneself," as in "He was born and raised in Baltimore, so his British accent seemed like an affectation."

Is affect a noun or a verb?

Affect is both a noun and a verb, but the verb is far more common; it means "to act on or change someone or something," as in "The change will affect everyone." The noun affect is used primarily in psychology contexts to refer to the facial expressions, gestures, postures, vocal intonations, etc., that typically accompany an emotion, as in "The patient had a flat affect."

Examples of affect in a Sentence

Verb (1) As strange as this sounds, the negative karma probably affected the actual games, the way a gambler who constantly dwells on his bad luck can derail an entire blackjack table. — Bill Simmons, ESPN, 24 June 2002 The Paris adventures of various Russians, including a romance for Dontsov, affect both the newly democratized ones and hard-line party members. — Stanley Kauffmann, New Republic, 27 Feb. 1995 These programs, known as secret warranties or silent recalls, often involve a problem that affects a vehicle's safety or performance but that isn't the cause of a formal Federal recall. Consumer Reports, December 1993 Noun There's a good plot and good writing here, but Mallory's gender neutrality, conspicuous in her lack of affect, makes her seem like a comic-book character. — Cynthia Crossen, Wall Street Journal, 5 Oct. 1994 Many of these young killers display an absence of what psychiatrists call affect. They show no discernible emotional reaction to what they have done. — Richard Stengel, Time, 16 Sept. 1985 The way people respond to this is sometimes called "depressed affect"—a sort of mental shifting into neutral that psychologists say also happens to prisoners of war, submarine crews, and other people in confined situations with little stimulus. — Susan West, Science 84, January/February 1984 Verb (2) She pauses and affects the more dramatic tone of a veteran actress. — Chris Mundy, Rolling Stone, 15 June 1995 She doesn't put herself down, but she does affect a languid Valley Girl drawl to offset the sharpness of her observations … — Ken Tucker, Entertainment Weekly, 7 Oct. 1994 That is all I have, I said, affecting a pathos in my voice. — Flann O'Brian, At Swim-Two-Birds, 1939
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Recent Examples on the Web: Verb Europe's decision to reject Trump's confrontation with China and the WHO will affect both parties vying to win this year's US election. Nic Robertson, CNN, "The pandemic could reshape the world order. Trump's chaotic strategy is accelerating US losses," 23 May 2020 But the restrictions don’t affect everyone equally. Popular Science, "COVID-19 is setting back recovery from opioid addiction," 23 May 2020 That will affect the drinks industry for years to come, because peak alcohol consumption has traditionally been between the ages of 18 and 34. The Economist, "Schumpeter Farewell for now to a golden age of drinking," 23 May 2020 Possibly affecting the ambience was a set visit from Pinkett. Derek Lawrence,, "The untold stories of Independence Day, from humping dogs to bad makeout sessions," 22 May 2020 Their deaths have affected their children and family around the world, from France to Iraq. Niraj Warikoo, Detroit Free Press, "Chaldean immigrant parents in Michigan die from coronavirus, leaving behind 3 kids," 22 May 2020 That ultimately affects the alcohol content, acidity level and the color of wine. Mélissa Godin, Time, "'The Taste of Bordeaux Is Going to Change.' Under Threat From Climate Change and Coronavirus, French Winemakers Try Experimenting," 22 May 2020 In cities like New York, Chicago and the District, coronavirus deaths were disproportionately affecting black and brown communities. Washington Post, "How the coronavirus exposed health disparities in communities of color," 22 May 2020 The order affects night clubs, concert venues, theaters, auditoriums, performing arts centers, tourist attractions (including museums), racetracks, indoor children’s play areas, adult entertainment venues, casinos, bingo halls and social clubs. al, "Entertainment venues, museums to remain closed in Jefferson County," 22 May 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'affect.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of affect

Verb (1)

15th century, in the meaning defined above


14th century, in the meaning defined at sense 2

Verb (2)

15th century, in the meaning defined at transitive sense 6

History and Etymology for affect

Verb (1)

Middle English affecten, borrowed from Latin affectus, past participle of afficere "to produce an effect on, exert an influence on," from ad- ad- + facere "to do, make, bring about" — more at fact


Middle English, "capacity for emotion, emotion, desire, will," borrowed from Latin affectus "mental state, mood, feeling, affection," from afficere "to produce an effect on, exert an influence on" + -tus, suffix of verbal action — more at affect entry 1

Verb (2)

Middle English affecten "to desire," borrowed from Anglo-French affeter, affecter "to change, seek after," borrowed from Latin affectāre "to try to accomplish, strive after, pretend to have," frequentative derivative of afficere "to produce an effect on, exert an influence on" — more at affect entry 1

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Learn More about affect

Time Traveler for affect

Time Traveler

The first known use of affect was in the 14th century

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Statistics for affect

Last Updated

26 May 2020

Cite this Entry

“Affect.” Dictionary, Merriam-Webster, Accessed 28 May. 2020.

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More Definitions for affect


af·​fect | \ ə-ˈfekt How to pronounce affect (audio) \
affected; affecting

Kids Definition of affect

 (Entry 1 of 2)

: to pretend that a false behavior or feeling is natural or genuine She affected surprise upon hearing the news.


affected; affecting

Kids Definition of affect (Entry 2 of 2)

1 : to have an effect on I hope this disagreement won't affect our friendship. The oceans are affected by the moon.
2 : to cause strong emotions in … the Tin Woodman … was strongly affected by this sad speech.— L. Frank Baum, The Marvelous Land of Oz
3 : to cause illness in Rabies can affect dogs and cats.


af·​fect | \ ˈaf-ˌekt How to pronounce affect (audio) \

Medical Definition of affect

 (Entry 1 of 2)

: the conscious subjective aspect of an emotion considered apart from bodily changes also : a set of observable manifestations of a subjectively experienced emotion … patients … showed perfectly normal reactions and affects— Oliver Sacks
af·​fect | \ ə-ˈfekt, a- How to pronounce affect (audio) \

Medical Definition of affect (Entry 2 of 2)

: to produce an effect upon especially : to produce a material influence upon or alteration in paralysis affected his limbs

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More from Merriam-Webster on affect

Thesaurus: All synonyms and antonyms for affect

Rhyming Dictionary: Words that rhyme with affect

Spanish Central: Translation of affect

Nglish: Translation of affect for Spanish Speakers

Britannica English: Translation of affect for Arabic Speakers

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