ENGLISH
REFERENCE

adult

n. · adj. · v.
US //ˈædəɫt// UK //ˈædʌlt// adult
  1. 1 a grown person (n.)
    A2 Elementary

    a person who is fully grown or has reached the legal age to be responsible for themselves.

    a human being who has reached the legal age of majority or is physically and mentally mature.

    Example

    The museum ticket is ten dollars for an adult and five dollars for a child.

    Example

    In many jurisdictions, a person is legally considered an adult at eighteen, granting them the right to vote and enter into binding contracts.
    • grown up
  2. 2 mature animal (n.)
    B2 Upper Intermediate Technical Science

    an animal or plant that is fully grown and can produce young.

    an organism that has reached its final stage of development and is capable of reproduction.

    Example

    The adult butterfly looks very different from the caterpillar it used to be.

    Example

    The researchers monitored the migration patterns of adult salmon as they returned to their natal streams to spawn.
    • mature organism
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  1. 3 fully grown (adj.)
    A2 Elementary

    having reached full size or maturity.

    having attained full physical growth or development.

    Example

    An adult male elephant can weigh over six thousand kilograms.

    Example

    The sanctuary provides a safe environment for adult tigers that were rescued from illegal private collections.
  2. 4 age-restricted (adj.)
    B1 Intermediate

    meant only for adults, often because it contains violence or sexual content.

    intended for or restricted to adults, typically due to mature themes, sexual content, or graphic violence.

    Example

    The movie was rated R, meaning it was for an adult audience only.

    Example

    The bookstore has a separate section for adult fiction that explores complex political and social themes unsuitable for younger readers.
    • family friendly
  3. 5 to act responsibly (v.)
    C1 Advanced Informal Slang

    to do the boring but necessary things that grown-ups have to do, like paying bills.

    to behave in a manner characteristic of a responsible adult, especially by performing mundane or difficult tasks.

    Example

    I am not ready to adult today; I just want to stay in bed.

    Example

    After a long week of adulting—paying taxes, fixing the car, and grocery shopping—she spent the entire Sunday playing video games.

    Usage

    Often used in the continuous form 'adulting'.

    Teacher's tip

    This is a modern, humorous term used by young adults to describe the struggle of daily responsibilities.
    • be responsible
Origin

From French adulte, from Latin adultus (“grown up”), perfect passive participle of adolescō (“I grow up”). Compare adolescent.

Idioms1 entry

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