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functional

adj. · n.
US //ˈfəŋkʃənəɫ// UK //fˈʌŋkʃənəl// func·tion·al
  1. 1 working correctly (adj.)
    B2 Upper Intermediate

    working correctly and ready to use.

    in good working order; operational and performing its intended task.

    Example

    The elevator is finally functional again after being broken for a week.

    Example

    Engineers worked through the night to ensure the cooling system was fully functional before the reactor was brought back online.
  2. 2 practical and useful (adj.)
    B2 Upper Intermediate

    designed to be useful and practical rather than just attractive.

    designed for utility and purpose rather than aesthetic appeal.

    Example

    The furniture in the office is functional but not very comfortable.

    Example

    The architect prioritised a functional layout that facilitated easy movement between departments over more decorative, traditional design elements.
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  1. 3 relating to a role (adj.)
    C1 Advanced Academic

    relating to the specific job or purpose someone or something has.

    relating to a specific function, role, or office.

    Example

    The manager has a functional responsibility to oversee the budget.

    Example

    The restructuring aimed to clarify functional boundaries between the research and development teams to prevent overlapping duties.
  2. 4 medical symptoms (adj.)
    C2 Proficiency Technical Medicine

    used to describe health problems that affect how the body works but do not show physical damage.

    referring to symptoms or disorders that affect physiological performance without an apparent organic or structural cause.

    Example

    The doctor explained that his stomach pain was a functional disorder caused by stress.

    Example

    Functional neurological disorders can present with significant motor impairment despite the absence of visible lesions on a standard MRI scan.
  3. 5 programming style (adj.)
    C1 Advanced Technical Computing

    a way of writing computer code based on mathematical functions.

    relating to a programming paradigm that treats computation as the evaluation of mathematical functions and avoids changing-state and mutable data.

    Example

    Functional programming languages like Haskell are popular for complex data analysis.

    Example

    The team decided to adopt a functional approach for the new microservice to minimize side effects and improve code testability.
  4. 6 math function (n.)
    C2 Proficiency Technical Math

    a special type of mathematical rule that takes a function as its input.

    a function whose domain is a set of functions and whose range is a set of scalars.

    Example

    In his advanced math class, he learned how to calculate a linear functional.

    Example

    The researcher defined a functional that mapped each continuous path to its total energy consumption over a fixed interval.
Origin

From function + -al.

Word family

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