probability

From Middle French probabilité, from Latin probābilitās (“probability, credibility”), from probābilis (“probable, credible”).

• (Received Pronunciation) IPA^(key): /pɹɒbəˈbɪlɪti/
• (General American) IPA^(key): /pɹɑbəˈbɪlɪɾi/
• Hyphenation: prob‧a‧bil‧i‧ty

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• Rhymes: -ɪlɪti

probability (plural probabilities)

1. The state of being probable; likelihood.
   • 1682, John Dryden, Religio Laici: Or, A Layman’s Faith, London: H. Hills, published 1710, page 21:

     Thus, firſt Traditions were a proof alone; / Cou’d we be certain ſuch they were ſo known: / But ſince ſome Flaws in long deſcent may be, / They make not Truth but Probability.

   • 1690, John Locke, “Of Probability”, in An Essay Concerning Humane Understanding, 3rd edition, London: Awnsham and John Churchil, published 1695, book IV, page 376:

     As Demonſtration is the ſhewing the agreement, or diſagreement of two Ideas, by the intervention of one or more Proofs, which have a conſtant, immutable, and viſible connexion one with another : ſo Probability is nothing but the appearance of ſuch an agreement, or diſagreement, by the intervention of Proofs, whoſe connexion is not conſtant and immutable, or at leaſt is not perceived to be ſo, but is, or appears for the moſt part to be ſo, and is enough to induce the Mind to judge the Propoſition to be true, or falſe, rather than the contrary.

2. An event that is likely to occur.
   • 1625, Capt. John Smith, The Trve Travels, Adventvres and Observations, volume I, Richmond: William W. Gray, published 1819, book II, page 115:

     These waters wash from the rocks such glistering tinctures, that the ground in some places seemeth as guilded, that better iudgements then ours might haue been perswaded, they contained more then probabilities.

3. The relative likelihood of an event happening.
4. (mathematics) A number, between 0 and 1, expressing the precise likelihood of an event happening.

   The probability of an event A occurring is denoted P(A).

• probable

• odds
• possibility
• verisimilitude
• credence

• probability at OneLook Dictionary Search
• probability in Webster’s Revised Unabridged Dictionary, G. & C. Merriam, 1913.
• probability in The Century Dictionary, The Century Co., New York, 1911