insurgent vs seditious

insurgent is a noun but seditious is not a noun.

Word	Noun	Adjective	Verb	Adverb
insurgent	Yes	Yes	No	No
seditious	No	Yes	No	No

As adjectives, insurgent and seditious are synonyms defined as:

insurgent and seditious: in opposition to a civil authority or government

Other synonyms of insurgent include subversive.

insurgent (noun)	seditious (noun)
a person who takes part in an armed rebellion against the constituted authority (especially in the hope of improving conditions)
a member of an irregular armed force that fights a stronger force by sabotage and harassment

insurgent (adjective)	seditious (adjective)
in opposition to a civil authority or government	in opposition to a civil authority or government
	arousing to action or rebellion