fifth columnist vs traitor

fifth columnist and traitor both are nouns.

Word	Noun	Adjective	Verb	Adverb
fifth columnist	Yes	No	No	No
traitor	Yes	No	No	No

As nouns, traitor is a hypernym of fifth columnist; that is, traitor is a word with a broader meaning than fifth columnist:

fifth columnist: a member of a clandestine subversive organization who tries to help a potential invader
traitor: someone who betrays his country by committing treason

Other hypernyms of fifth columnist include treasonist.

fifth columnist (noun)	traitor (noun)
a member of a clandestine subversive organization who tries to help a potential invader	someone who betrays his country by committing treason
	a person who says one thing and does another