ENGLISH
REFERENCE

unpredictable

adj. · n.
US //ˌənpɹɪˈdɪktəbəɫ// UK //ʌnpɹɪdˈɪktəbəl// un·pre·dictable
  1. 1 not able to be foreseen (adj.)
    B2 Upper Intermediate

    describing something that changes so much you cannot guess what will happen next.

    not able to be foreseen or known beforehand; lacking a predictable pattern or consistency.

    Example

    The weather in the mountains is unpredictable, so you should bring a rain jacket.

    Example

    The stock market remained highly unpredictable throughout the fiscal year, defying the projections of even the most seasoned financial analysts.

  2. 2 behaving unexpectedly (adj.)
    B2 Upper Intermediate

    describing a person who often changes their mood or actions without warning.

    behaving in a way that is not easily anticipated; often used to describe temperament or personality.

    Example

    He is a talented actor, but his unpredictable temper makes him difficult to work with.

    Example

    The director found the lead actor's unpredictable outbursts exhausting, as they frequently disrupted the filming schedule and lowered the crew's morale.

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  1. 3 an unexpected thing (n.)
    C1 Advanced Formal

    a person or thing that you cannot predict.

    a person, thing, or event that is impossible to predict. Often used in the plural to describe general uncertainties.

    Example

    In politics, you must always be prepared for the unpredictable.

    Example

    The strategist argued that the success of the campaign depended on how well the team managed the various unpredictables of the local election cycle.

Origin

From un- + predictable.

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