government-in-exile vs regime

government-in-exile and regime both are nouns.

Word	Noun	Adjective	Verb	Adverb
government-in-exile	Yes	No	No	No
regime	Yes	No	No	No

As nouns, regime is a hypernym of government-in-exile; that is, regime is a word with a broader meaning than government-in-exile:

government-in-exile: a temporary government moved to or formed in a foreign land by exiles who hope to rule when their country is liberated
regime: the organization that is the governing authority of a political unit

Other hypernyms of government-in-exile include authorities, government.

government-in-exile (noun)	regime (noun)
a temporary government moved to or formed in a foreign land by exiles who hope to rule when their country is liberated	(medicine) a systematic plan for therapy (often including diet)
	the organization that is the governing authority of a political unit