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uncertainty

n.
US //ənˈsɝtənti// UK //ʌnsˈɜːtənti// un·cer·tain·ty
  1. 1 the state of being unsure (n.)
    B2 Upper Intermediate

    the feeling of not being sure about something or not knowing what will happen.

    the psychological state of doubt or lack of conviction regarding a fact or outcome. Uncountable in this abstract sense.

    Example

    There is a lot of uncertainty about whether the company will close next year.

    Example

    The prevailing sense of uncertainty among investors led to a sharp decline in market activity as they waited for the central bank's announcement.
  2. 2 an unpredictable factor (n.)
    B2 Upper Intermediate

    a specific thing or situation that is not known or decided yet.

    a specific circumstance or variable that is unknown or unpredictable. Countable in this sense.

    Example

    Life is full of uncertainties, so it is important to have a backup plan.

    Example

    The project manager attempted to account for every possible uncertainty, from supply chain delays to sudden shifts in local regulations.
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  1. 3 measurement error (n.)
    C1 Advanced Technical Science

    the range of possible error in a scientific measurement.

    a parameter that quantifies the dispersion of values that could reasonably be attributed to a measured quantity.

    Example

    The scientist calculated the uncertainty in the temperature readings to ensure the data was accurate.

    Example

    Standard laboratory protocols require researchers to report the degree of uncertainty associated with their experimental results to maintain scientific rigour.

    Usage

    Often used with the preposition 'in' followed by the measured variable.
Origin

From Middle English uncerteynte; equivalent to un- + certainty or uncertain + -ty.

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