judicial separation vs fiat

judicial separation and fiat both are nouns.

Word	Noun	Adjective	Verb	Adverb
judicial separation	Yes	No	No	No
fiat	Yes	No	No	No

As nouns, fiat is a hypernym of judicial separation; that is, fiat is a word with a broader meaning than judicial separation:

judicial separation: a judicial decree regulating the rights and responsibilities of a married couple living apart
fiat: a legally binding command or decision entered on the court record (as if issued by a court or judge)

Other hypernyms of judicial separation include decree, edict, order, rescript.

judicial separation (noun)	fiat (noun)
a judicial decree regulating the rights and responsibilities of a married couple living apart	a legally binding command or decision entered on the court record (as if issued by a court or judge)