a posteriori

a pos·​te·​ri·​o·​ri | \ ˌä-(ˌ)pō-ˌstir-ē-ˈȯr-ē How to pronounce a posteriori (audio) , -ˌster-; ˌā-(ˌ)pä-ˌstir-ē-ˈȯr-ˌī How to pronounce a posteriori (audio) , -(ˌ)pō-, -ˈȯr-ē \

Definition of a posteriori

2 : relating to or derived by reasoning from observed facts — compare a priori

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Other Words from a posteriori

a posteriori adverb

Did You Know?

A posteriori, Latin for "from the latter", is a term from logic, which usually refers to reasoning that works backward from an effect to its causes. This kind of reasoning can sometimes lead to false conclusions. The fact that sunrise follows the crowing of a rooster, for example, doesn't necessarily mean that the rooster's crowing caused the sun to rise.

Examples of a posteriori in a Sentence

Recent Examples on the Web This a posteriori saga gives us a refreshed Raphael, whose psychological acuity feels newly approachable. Roberta Smith, New York Times, "Best Art Books of 2020," 26 Nov. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'a posteriori.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of a posteriori

1588, in the meaning defined at sense 1

History and Etymology for a posteriori

borrowed from Medieval Latin ā posteriōrī literally, "from what is later"

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Time Traveler for a posteriori

Time Traveler

The first known use of a posteriori was in 1588

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Statistics for a posteriori

Last Updated

30 Nov 2020

Cite this Entry

“A posteriori.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/a%20posteriori. Accessed 27 Jan. 2021.

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More Definitions for a posteriori

a posteriori

How to pronounce a posteriori (audio) How to pronounce a posteriori (audio)

English Language Learners Definition of a posteriori

formal : relating to what can be known by observation rather than through an understanding of how certain things work

More from Merriam-Webster on a posteriori

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Nglish: Translation of a posteriori for Spanish Speakers

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