probability

/ˈprɑbəˌbɪlədi/

/prɒbəˈbɪlɪti/

Other forms: probabilities

Probability has to do with how likely something is to happen. If there's a 50/50 chance, then the probability is 50%.

Probability is a part of math involving percentages and chance. The probability of a thing happening is the same as the odds or chances of something happening. When you watch a weather forecast, it might say there's a 30% chance of showers; that's probability. Gambling — on sports or something else — is also based on probability. Since most things in life are uncertain, it's helpful to know if the probability is high or low for things you want to do or try.

Definitions of probability

1. noun

   a measure of how likely it is that some event will occur; a number expressing the ratio of favorable cases to the whole number of cases possible
   “the probability that an unbiased coin will fall with the head up is 0.5”

   synonyms: chance

   types:

   conditional probability, contingent probability

   the probability that an event will occur given that one or more other events have occurred

   cross section

   (physics) the probability that a particular interaction (as capture or ionization) will take place between particles; measured in barns

   exceedance

   (geology) the probability that an earthquake will generate a level of ground motion that exceeds a specified reference level during a given exposure time

   fair chance, sporting chance

   a reasonable probability of success

   fat chance, slim chance

   little or no chance of success

   joint probability

   the probability of two events occurring together

   risk, risk of exposure

   the probability of being exposed to an infectious agent

   risk, risk of infection

   the probability of becoming infected given that exposure to an infectious agent has occurred

   type of:

   amount, measure, quantity

   how much there is or how many there are of something that you can quantify
2. noun

   the quality of being probable; a probable event or the most probable event
   “for a while mutiny seemed a probability”

   “going by past experience there was a high probability that the visitors were lost”

   antonyms:

   improbability

   the quality of being improbable

   types:

   likelihood, likeliness

   the probability of a specified outcome

   odds

   the likelihood of a thing occurring rather than not occurring

   type of:

   quality

   an essential and distinguishing attribute of something or someone