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optional

adj. · n.
US //ˈɑpʃənəɫ// UK //ˈɒpʃənəl// op·tion·al
  1. 1 not compulsory (adj.)
    B1 Intermediate

    describes something you can choose to do or not do.

    denoting something that is left to choice rather than being required or mandatory.

    Example

    The school trip is optional, so you don't have to go if you are busy.

    Example

    While the core modules are mandatory for graduation, the advanced seminar remains optional for those seeking additional credits.

    Usage

    Usually placed before the noun it modifies.
  2. 2 an elective item (n.)
    B2 Upper Intermediate

    something that is not required, like an extra subject at school.

    an item, such as a course of study or a vehicle feature, that is not compulsory.

    Example

    Leather seats are one of the many expensive optionals available for this car.

    Example

    The curriculum includes three core sciences and a wide variety of optionals ranging from art history to computer science.

    Usage

    Often used in the plural when referring to car features or school subjects.
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  1. 3 programming variable (n.)
    C1 Advanced Technical Computing

    a type of data in computer code that might or might not have a value.

    a container or wrapper type that may or may not contain a meaningful value, used to handle null cases safely.

    Example

    The function returns an optional because the user might not have an email address.

    Example

    By using an Optional instead of a null pointer, the developer explicitly signals that the return value might be empty, reducing runtime errors.

    Usage

    Often capitalized when referring to the specific class or type in languages like Swift or Java.

    Teacher's tip

    This is a highly specific technical term; outside of software engineering, 'optional' is almost exclusively an adjective.
    • nullable
    • maybe type
Origin

From option + -al.

Word family

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