# probability

## noun

prob·​a·​bil·​i·​ty
plural probabilities
1
a(1)
: the chance that a given event will occur
(2)
: the ratio of the number of outcomes in an exhaustive set of equally likely outcomes that produce a given event to the total number of possible outcomes
b
: a branch of mathematics concerned with the study of probabilities
2
: something (such as an event or circumstance) that is probable
3
: the quality or state of being probable
4
: a logical relation between statements such that evidence confirming one confirms the other to some degree

## Example Sentences

There is a low probability that you will be chosen. There is some probability of rain tomorrow. With the dark clouds moving in, rain seems more like a probability than a possibility. The probability of a coin coming up heads is one out of every two tries.
Recent Examples on the Web Derivative markets now imply a 60% probability of a quarter-point rate hike in June, with the remaining odds favoring a pause. WSJ, 30 May 2023 Just before the Commerce Department data was released on Friday, markets had the probability of a Fed pause at 54.2%, according to CME FedWatch. Alicia Wallace, CNN, 26 May 2023 An economic model used by the Conference Board, a business research group, puts the probability of a U.S. recession over the next year at 99%. CBS News, 2 May 2023 The probability of rain in Boston is 60 percent or greater for all of Sunday, according to the weather service. Haley Hersey, BostonGlobe.com, 30 Apr. 2023 However, that doesn’t eliminate the probability of some bad outcomes. Christina Hall, Detroit Free Press, 27 Apr. 2023 Much of the southern half of Alabama will have a 50 to 60 percent chance, and areas closer to the coast could have a 40-50 percent probability. Leigh Morgan, al, 22 Apr. 2023 One is the probability that the majority — maybe the vast majority — of federal student loan borrowers don’t have credit scores anything like the 773 average that SoFi’s current student loan borrowers maintain. Ron Lieber, New York Times, 22 Apr. 2023 According to the referendum language, these circumstances are prior convictions for a violent crime, the probability that the accused will fail to appear in court, the need to protect the community from serious harm and prevent witness intimidation. Hunter Turpin, Journal Sentinel, 4 Apr. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'probability.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

## Word History

First Known Use

15th century, in the meaning defined at sense 3

Time Traveler
The first known use of probability was in the 15th century

probability

## Cite this Entry

“Probability.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/probability. Accessed 8 Jun. 2023.

## Kids Definition

probability

noun
prob·​a·​bil·​i·​ty
plural probabilities
1
: the quality or state of being probable
2
: something probable
3
a
: a measure of how often a particular event will happen if something which results in any of a number of possible events is done repeatedly
the probability of a coin coming up heads is ½
b
: a branch of mathematics concerned with the study of probabilities

## More from Merriam-Webster on probability

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