Dictionary

¹ex post facto

adverb ex post fac·to \ˌeks-ˌpōs(t)-ˈfak-(ˌ)tō\

Definition of EX POST FACTO

: after the fact : retroactively

See ex post facto defined for kids

Late Latin, literally, from a thing done afterward

First Known Use: 1621

adjective

: done, made, or formulated after the fact : retroactive <ex post facto approval> <ex post facto laws>

1787

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