probability

American  

[prob-uh-bil-i-tee] / ˌprɒb əˈbɪl ɪ ti /

noun

plural

probabilities

1. the quality or fact of being probable.

2. a strong likelihood or chance of something.

   The probability of the book's success makes us optimistic.

3. a probable event, circumstance, etc..

   Our going to China is a probability.

4. Statistics.

   1. the relative possibility that an event will occur, as expressed by the ratio of the number of actual occurrences to the total number of possible occurrences.

   2. the relative frequency with which an event occurs or is likely to occur.

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idioms

1. in all probability, very probably; quite likely.

   The factory will in all probability be relocated.

probability British  

/ ˌprɒbəˈbɪlɪtɪ /

noun

1. the condition of being probable

2. an event or other thing that is probable

3. statistics a measure or estimate of the degree of confidence one may have in the occurrence of an event, measured on a scale from zero (impossibility) to one (certainty). It may be defined as the proportion of favourable outcomes to the total number of possibilities if these are indifferent ( mathematical probability ), or the proportion observed in a sample ( empirical probability ), or the limit of this as the sample size tends to infinity ( relative frequency ), or by more subjective criteria ( subjective probability )

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probability Scientific  

/ prŏb′ə-bĭl′ĭ-tē /

1. A number expressing the likelihood of the occurrence of a given event, especially a fraction expressing how many times the event will happen in a given number of tests or experiments. For example, when rolling a six-sided die, the probability of rolling a particular side is 1 in 6, or 1/6.

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probability Cultural  

1. A number between zero and one that shows how likely a certain event is. Usually, probability is expressed as a ratio: the number of experimental results that would produce the event divided by the number of experimental results considered possible. Thus, the probability of drawing the ten of clubs from an ordinary deck of cards is one in fifty-two (1:52), or one fifty-second.

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probability More Idioms  

1. see in all probability.

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Other Word Forms

• nonprobability noun
• superprobability noun

Etymology

Origin of probability

From the Latin word probābilitās, dating back to 1545–55. See probable, -ity

Example Sentences

Our recommendations support the use of probabilities instead of dichotomous “p-values” and the inclusion of findings from related studies to evaluate safety and effectiveness—an invaluable advancement for rare-disease research.

From The Wall Street Journal

As of Thursday afternoon, traders on Kalshi put a 38% probability that Iran will close the Strait of Hormuz this year.

From The Wall Street Journal

“It’s very easy to understand these binary probabilities—is this event going to happen or isn’t it?”

From The Wall Street Journal

Nevertheless, an analysis of the last months of prior Fed chairs suggests that the probability of a higher fed funds rate in three months, while perhaps small, is still greater than zero.

From MarketWatch

Using these improved statistical models, the researchers derived analytical expressions for error and sift probabilities under pointing error, marking a first for the field.

From Science Daily

Related Words

• anticipation
• chance
• contingency
• expectation
• feasibility
• odds
• possibility
• prospect