citizen vs thane

citizen and thane both are nouns.

Word	Noun	Adjective	Verb	Adverb
citizen	Yes	No	No	No
thane	Yes	No	No	No

As nouns, thane is a hyponym of citizen; that is, thane is a word with a more specific, narrower meaning than citizen:

citizen: a native or naturalized member of a state or other political community
thane: a man ranking above an ordinary freeman and below a noble in Anglo-Saxon England (especially one who gave military service in exchange for land)

Other hyponyms of citizen include active citizen, civilian, freeperson, private citizen, repatriate, elector, voter.

citizen (noun)	thane (noun)
a native or naturalized member of a state or other political community	a man ranking above an ordinary freeman and below a noble in Anglo-Saxon England (especially one who gave military service in exchange for land)
	a feudal lord or baron