probability

noun

plural probabilities
Synonyms of probability
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

Synonyms of probability

Examples of probability in a Sentence

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
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Listed at +510 odds that give them around a 15 percent implied probability to win, major sportsbooks like DraftKings aren’t ruling the Steelers out, and neither is The Athletic’s predictive analyst Austin Mock. Austin Mock, New York Times, 25 Aug. 2026 Among Ashkenazi Jews, however, the probability of carrying this mutation is 10 times higher, occurring in 1 out of 40 individuals. Larry Luxner, Sun Sentinel, 25 Aug. 2026 The objective is to allocate capital where each dollar has the highest probability of creating long-term shareholder value. Robert Daugherty, Forbes.com, 23 Aug. 2026 The new math standards called for data analysis and probability to be incorporated into mathematics education beginning in the early grades, including kindergarten. Mary Jean Tecce Decarlo, The Conversation, 20 Aug. 2026 See All Example Sentences for probability

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

Browse Nearby Words

Cite this Entry

“Probability.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/probability. Accessed 1 Sep. 2026.

Kids Definition

probability

noun
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

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