Probability
The extent to which something is probable; the likelihood of something happening or being the case.
In mathematics, probability is a numerical measure (between 0 and 1) of the likelihood of an event occurring. It's used to quantify uncertainty.
Word relationships
- likelihood: Likelihood is a general term for how probable something is; probability is often a specific numerical measure.
- chance: Chance can be used informally for probability, but 'probability' is the formal, mathematical term.
- impossibility: Impossibility means something cannot happen, while probability measures how likely it is to happen.
- certainty: Certainty means something will definitely happen (probability of 1), while probability deals with events that are not certain.
Commonly confused with
- Possibility: Possibility refers to whether something can happen, while probability refers to how likely it is to happen, often with a numerical value.
Word family
- probable (adjective): Likely to happen or be true.
- probably (adverb): Almost certainly; as far as one can tell.
Collocations
- high probability
- low probability
- probability theory
- conditional probability
- joint probability
Idioms & expressions
- in all probability
Example sentences
- "The probability of rolling a six on a fair die is one-sixth." Explaining a statistical concept.
- "Despite the low probability of a major earthquake, residents were advised to have emergency kits ready." Discussing real-world risk.
- "Actuaries specialize in calculating the probability of future events, such as accidents or deaths, for insurance purposes." Referring to a field of study.
Memory hook
Think 'PROB-ability' as the 'PROBable' outcome, or 'PROBING' how likely something is. Likely-test
When not to use
Avoid using 'probability' when you mean 'possibility' if you're not referring to a quantifiable likelihood. 'Possibility' is more general and doesn't imply a numerical measure.
Fun facts
- The mathematical theory of probability originated in the 17th century from correspondence between Pierre de Fermat and Blaise Pascal concerning gambling problems.
- Probability is fundamental to fields like quantum mechanics, finance, and artificial intelligence.
Related words
Explore more words
stochastic, prospect, contingent, Risk, contingency, aleatory
Also appears in
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