Definition of probability
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.
First Known Use of probability
PROBABILITY Defined for English Language Learners
Definition 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
Definition of probability for Students
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.>
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