Definition of probability
probabilities
1 : the quality or state of being probable
2 : something (as an event or circumstance) that is probable
3 a (1) : 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 (2) : the chance that a given event will occur b : a branch of mathematics concerned with the study of probabilities
4 : a logical relation between statements such that evidence confirming one confirms the other to some degree
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.
15th Century
First Known Use of probability
15th century
Other Mathematics and Statistics Terms
PROBABILITY Defined for English Language Learners
probability
playDefinition of probability for English Language Learners

: the chance that something will happen

: something that has a chance of happening

: a measure of how often a particular event will happen if something (such as tossing a coin) is done repeatedly
PROBABILITY Defined for Kids
probability
playDefinition of probability for Students
probabilities
1 : the chance of happening <The probability of rain is low.>
2 : something likely <Rain is a probability.>
3 : a measure of how likely a given event is <The probability of a coin landing face up is 1⁄2.>
Learn More about probability

Thesaurus: All synonyms and antonyms for probability Spanish Central: Translation of probability Nglish: Translation of probability for Spanish speakers Britannica English: Translation of probability for Arabic speakers Britannica.com: Encyclopedia article about probability
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