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Synonyms

affect

1 American  
[uh-fekt, af-ekt] / əˈfɛkt, ˈæf ɛkt /

verb (used with object)

  1. to act on; produce an effect or change in.

    Cold weather affected the crops.

    Synonyms:
    alter, modify, sway, influence
  2. to impress the mind or move the feelings of.

    The music affected him deeply.

    Synonyms:
    stir, touch
  3. (of pain, disease, etc.) to attack or lay hold of.


noun

  • affects
    plural
  1. Psychology. feeling or emotion.

  2. Psychiatry. an expressed or observed emotional response.

    Restricted, flat, or blunted affect may be a symptom of mental illness, especially schizophrenia.

  3. Obsolete. affection; passion; sensation; inclination; inward disposition or feeling.

affect 2 American  
[uh-fekt] / əˈfɛkt /

verb (used with object)

  1. to give the appearance of; pretend or feign.

    to affect knowledge of the situation.

  2. to assume artificially, pretentiously, or for effect.

    to affect a Southern accent.

  3. to use, wear, or adopt by preference; choose; prefer.

    the peculiar costume he affected.

  4. to assume the character or attitude of.

    to affect the freethinker.

  5. (of things) to tend toward habitually or naturally.

    a substance that affects colloidal form.

  6. (of animals and plants) to occupy or inhabit; live in or on.

    Lions affect Africa. Moss affects the northern slopes.

  7. Archaic.

    1. to have affection for; fancy.

    2. to aim at; aspire to.


verb (used without object)

  1. Obsolete. to incline, tend, or favor (usually followed byto ).

    He affects to the old ways.

affect 1 British  
/ əˈfɛkt /

verb

  1. to put on an appearance or show of; make a pretence of

    to affect ignorance

  2. to imitate or assume, esp pretentiously

    to affect an accent

  3. to have or use by preference

    she always affects funereal clothing

  4. to adopt the character, manner, etc, of

    he was always affecting the politician

  5. (of plants or animals) to live or grow in

    penguins affect an arctic climate

  6. to incline naturally or habitually towards

    falling drops of liquid affect roundness

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

affect 2 British  

verb

  1. to act upon or influence, esp in an adverse way

    damp affected the sparking plugs

  2. to move or disturb emotionally or mentally

    her death affected him greatly

  3. (of pain, disease, etc) to attack

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

noun

  1. psychol the emotion associated with an idea or set of ideas See also affection

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Usage

What's the difference between affect and effect? Affect is most commonly used as a verb meaning to act on or produce a change in someone or something. Effect is most commonly used as a noun meaning a result or consequence. Remembering the difference between the words can be especially hard because these senses of the words have just about the same pronunciation. Complicating things further is the fact that affect can also be used as a noun (referring to a state of emotion, as in He had a sad affect) and effect can also be used as a verb (meaning to make happen, as in We can only effect change by taking action). However, these senses of the words are much less commonly used. You can remember that affect is most commonly used as a verb because it begins with a, for action. You can also remember how affect and effect are most commonly used by using the acronym RAVEN:R = RememberA = Affect is aV = VerbE = Effect is aN = NounHere’s an example of affect and effect used correctly in the same sentence. Example: It’s unclear what immediate effects the new law will have or how it will affect future generations. Want to learn more? Read the full breakdown of the difference between affect and effect.

Commonly Confused

Affect1 and effect, each both noun and verb, share the sense of “influence,” and because of their similarity in pronunciation are sometimes confused in writing. As a verb affect1 means “to act on” or “to move” ( His words affected the crowd so deeply that many wept ); affect2 means “to pretend” or “to assume” ( new students affecting a nonchalance they didn't feel ). The verb effect means “to bring about, accomplish”: Her administration effected radical changes. The noun effect means “result, consequence”: the serious effects of the oil spill. The noun affect1 pronounced with the stress on the first syllable, is a technical term in psychology and psychiatry. Affect2 is not used as a noun.

See affect 1.

Synonym Usage

See pretend.

Other Word Forms

Derived Forms

Inflected Forms

Nouns

Etymology

Origin of affect1

First recorded in 1350–1400; Middle English, from Latin affectus “acted upon, subjected to; mental or emotional state” (past participle and action noun of afficere ), equivalent to af- “toward” + fec- (combining form of facere “to make, do”) + -tus action noun suffix or -tus past participle suffix; see af-

Origin of affect2

First recorded in 1400–50; late Middle English, from Middle French affecter, from Latin affectāre “to strive after, feign” (frequentative of afficere “to do to”), equivalent to af- af- + fec- ( see affect 1) + -tāre frequentative suffix

Explanation

Affect is most often used as a verb meaning “to have an impact on,” as in “The tornado barreling towards us will affect our picnic plans.” As a verb, affect can also mean “to feign an appearance,” as in, “Don’t let that surfer’s California accent fool you. Although she affects a convincing ‘Dude, that was rad,’ she is from Minnesota and just moved out West last month.” Don’t let that affect your friendship, though, she’s probably really fun.

Keep Reading on Vocabulary.com

Vocabulary lists containing affect

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Then, there are energy costs, which affect JLR and its rivals.

From BBC Sep. 7, 2026

The protest was organised by Democratism, an initiative that, according to its website, aims to launch debate "on how AI and robotisation affect the labour market".

From Barron's Sep. 7, 2026

Obviously, many factors affect couples’ home-buying and family-size decisions, and K-12 scholarship programs alone probably won’t solve America’s housing-affordability and fertility challenges.

From The Wall Street Journal Sep. 6, 2026

The centers require intense cooling, which often demands high water and power use and creates the potential to affect the environment and to pass on utility costs to consumers.

From Los Angeles Times Sep. 6, 2026

The ice never melts; it clings to the bottom of the world, spawning winds, storms, and weather that affect the whole planet.

From "Shipwreck at the Bottom of the World" by Jennifer Armstrong

Some employers offer extra parental leave to their workers, but most people earn less when on maternity or paternity leave, which affects how much leave many fathers take.

From BBC Sep. 5, 2026

Her lawyers say this was caused by postpartum psychosis, a condition that experts say affects about one to two women in every 1,000 births.

From Barron's Sep. 4, 2026

While BRP raised full-year guidance, Hardiman says it is still unclear “how much of a role the everchanging tariff landscape” affects outlook.

From The Wall Street Journal Sep. 4, 2026

Aging happens at different speeds from one person to another, but it eventually affects everyone.

From Science Daily Sep. 3, 2026

The disease affects at least one teenaged American girl every 30 seconds.

From "Everything, Everything" by Nicola Yoon

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