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probability

n.
US //ˌpɹɑbəˈbɪɫəˌti// UK //pɹˌɒbəbˈɪlɪti// prob·a·bil·i·ty
  1. 1 likelihood (n.)
    B2 Upper Intermediate

    the chance that something will happen or is true.

    the quality or state of being probable; the extent to which something is likely to happen.

    Example

    There is a high probability of rain this afternoon, so take an umbrella.

    Example

    The probability of a successful merger remains high, provided that both boards agree on the final valuation by the end of the quarter.
    Pitfall
    There is a high probability for rain today.
    There is a high probability of rain today.

    Use the preposition 'of' after probability to indicate what event is likely to happen.

  2. 2 mathematical value (n.)
    B2 Upper Intermediate Technical Math

    a number between 0 and 1 that shows exactly how likely something is.

    a precise numerical measure of the likelihood of an event, where 0 indicates impossibility and 1 indicates certainty.

    Example

    In this game, the probability of drawing a red card is exactly fifty percent.

    Example

    The algorithm calculates the probability of each outcome based on historical data sets and real-time variables.

    Usage

    Often used with 'of' followed by a gerund or noun phrase.
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  1. 3 a likely event (n.)
    C1 Advanced Formal

    something that is very likely to happen.

    a probable event or outcome; something that can reasonably be expected to occur.

    Example

    A change in the law is now a strong probability rather than just a hope.

    Example

    While a total market collapse is unlikely, a period of stagnation is a distinct probability that investors must prepare for.
Origin

From Middle French probabilité, from Latin probābilitās (“probability, credibility”), from probābilis (“probable, credible”).

Word family

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