secessionist vs exponent

secessionist and exponent both are nouns.

Word	Noun	Adjective	Verb	Adverb
secessionist	Yes	No	No	No
exponent	Yes	No	No	No

As nouns, exponent is a hypernym of secessionist; that is, exponent is a word with a broader meaning than secessionist:

Other hypernyms of secessionist include advocate, advocator, proponent.

secessionist (noun)	exponent (noun)
an advocate of secessionism	a mathematical notation indicating the number of times a quantity is multiplied by itself
	a person who pleads for a cause or propounds an idea
	someone who expounds and interprets or explains