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effect

n. · v.
US //ˈifɛkt// UK //ɪfˈɛkt// ef·fect
  1. 1 a result (n.)
    A2 Elementary

    a change or result that is caused by something else.

    a change which is a result or consequence of an action or other cause.

    Example

    The new law had a positive effect on the local economy.

    Example

    Scientists are still studying the long-term effects of microplastics on marine ecosystems and the broader food chain.

    Usage

    Commonly used with the preposition 'on'.
    Pitfall
    The medicine had a good affect on me.
    The medicine had a good effect on me.

    Use 'effect' as a noun for the result, and 'affect' as a verb for the action of changing something.

  2. 2 an influence (n.)
    B1 Intermediate

    the power to influence someone's feelings or thoughts.

    the power to produce an outcome or achieve a particular impression on the mind.

    Example

    The soft music had a calming effect on the crying baby.

    Example

    The speaker's words had a profound effect on the audience, inspiring many to volunteer for the charity immediately.
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  1. 3 in operation (n.)
    B2 Upper Intermediate Formal Law

    the state of being active or in use, like a rule or a law.

    the state of being operative or in force; often used in the phrases 'in effect' or 'to take effect'.

    Example

    The new tax rules will take effect from the start of next year.

    Example

    Although the policy is technically active, it has had little practical effect on the daily operations of the department.

    Usage

    Often follows the verbs 'take' or 'come into'.
  2. 4 visual/sound tricks (n.)
    B1 Intermediate

    an illusion created for a movie or a song using technology.

    an illusion produced by technical means, such as sound manipulation or computer-generated imagery.

    Example

    The special effects in the space movie looked incredibly realistic.

    Example

    The sound engineer added a reverb effect to the vocals to give the track a more ethereal and spacious quality.
  3. 5 personal belongings (n.)
    C1 Advanced Formal

    the things that you own and carry with you.

    personal property or belongings; almost exclusively used in the plural form.

    Example

    The hotel staff returned all his personal effects after he left them in the room.

    Example

    The insurance policy covers the loss of personal effects while traveling, provided they are kept in a secure location.

    Usage

    Usually appears as the fixed phrase 'personal effects'.
  4. 6 to bring about (v.)
    C1 Advanced Formal Academic

    to make something happen, especially a change.

    to cause something to happen; to bring about or implement a result.

    Example

    The new director hopes to effect significant changes within the company.

    Example

    The protesters argued that only a complete overhaul of the system could effect the social justice they demanded.

    Usage

    This is a transitive verb that usually takes 'change' or 'reforms' as an object.

    Teacher's tip

    Learners often confuse this with 'affect'. Remind them that 'to effect change' is a formal, specific collocation meaning 'to make change happen'.
Origin

Of the noun: from Middle English effect, from Old French effect (modern French effet), from Latin effectus (“an effect, tendency, purpose”), from efficiō (“accomplish, complete, effect”); see effect as a verb. Displaced Old English fremming, fremednes from fremman. Of the verb: from Middle English effecten, partly from Medieval Latin effectuō, from Latin effectus, perfect passive participle of efficiō (“accomplish, complete, do, effect”), from ex (“out”) + faciō (“do, make”) (see fact and compare affect, infect) and partly from the noun effect.

Idioms2 entries

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