ex post facto

[ eks -pohst -fak-toh ]
/ ˈɛks ˌpoʊst ˈfæk toʊ /
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from or by subsequent action; retroactively; subsequently; retrospectively.


having retroactive force; made or done subsequently: an ex post facto law.



In effect, this quiz will prove whether or not you have the skills to know the difference between “affect” and “effect.”
Question 1 of 7
The rainy weather could not ________ my elated spirits on my graduation day.

Origin of ex post facto

First recorded in 1625–35; from Latin: “from a thing done afterward, from what is done afterward”
ad hoc, a posteriori, a priori, ex post facto , prima facie
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

British Dictionary definitions for ex post facto

ex post facto
/ (ɛks pəʊst ˈfæktəʊ) /


having retrospective effectan ex post facto law
C17: from Latin ex from + post afterwards + factus done, from facere to do
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Cultural definitions for ex post facto (1 of 2)

ex post facto
[ (eks pohst fak-toh) ]

An explanation or regulation concocted after the event, sometimes misleading or unjust: “Your ex post facto defense won't stand up in court.” (See ex post facto law.) From Latin, meaning “after the deed.”

Cultural definitions for ex post facto (2 of 2)

ex post facto
[ (eks pohst fak-toh) ]

A descriptive term for an explanation or a law that is made up after an event and then applied to it: “The chairman's description of his plan sounds like an ex post facto attempt to justify an impulsive action.” Ex post facto is Latin for “from after the deed.”

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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