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affect

v. · n.
US //əˈfɛkt// af·fect
  1. 1 to cause emotion (v.)
    B2 Upper Intermediate

    to make someone feel a strong emotion, like sadness.

    to touch the feelings of someone; to move someone emotionally.

    Example

    The sad news about the accident affected everyone in the small town.

    Example

    The documentary about the refugee crisis deeply affected the audience, leaving many in tears as the credits began to roll.
  2. 2 to harm the body (v.)
    B2 Upper Intermediate Medicine

    when a disease or health problem attacks a part of the body.

    of a disease or medical condition: to infect or attack a specific organ or bodily system.

    Example

    The virus usually affects the lungs and makes it hard to breathe.

    Example

    While the primary infection was respiratory, the secondary symptoms began to affect the patient's nervous system within forty-eight hours.
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  1. 3 to pretend (v.)
    C1 Advanced Formal Literary

    to act in a way that is not natural for you to impress others.

    to assume a character or mannerism artificially; to make a pretense of.

    Example

    He affected a British accent to sound more sophisticated at the party.

    Example

    She affected an air of indifference toward the promotion, though her colleagues knew she had campaigned vigorously for the position.
  2. 4 outward emotion (n.)
    C2 Proficiency Academic Technical Psychology

    the way a person shows their feelings through their face or body.

    the external expression of emotion as observed by others, distinct from the internal experience of feeling.

    Example

    The doctor noticed that the patient had a flat affect and rarely smiled.

    Example

    The therapist noted the patient's incongruous affect, observing that he laughed while recounting traumatic childhood memories.

    Usage

    In this sense, the stress is on the first syllable (AF-fect).
Etymology 1

From Middle English affecten, from Latin affectāre, from Latin affectus, the participle stem of Latin afficere (“to act upon, influence, affect, attack with disease”), from ad- + facere (“to make, do”).

Etymology 2

From Middle English affecten, from Anglo-Norman affecter (“strive after”), Middle French affecter (“feign”), and their source, Latin affectāre (“to strive after, aim to do, pursue, imitate with dissimulation, feign”), frequentative of afficere (“to act upon, influence”) (see Etymology 1, above).

Etymology 3

From Middle English affect, from Latin affectus, adfectus (“a state of mind or body produced by some (external) influence, especially sympathy or love”), from afficere (“to act upon, influence”).

Word family

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