marchioness vs peeress

marchioness and peeress both are nouns.

Word	Noun	Adjective	Verb	Adverb
marchioness	Yes	No	No	No
peeress	Yes	No	No	No

As nouns, peeress is a hypernym of marchioness; that is, peeress is a word with a broader meaning than marchioness:

Other hypernyms of marchioness include Lady, noblewoman.

marchioness (noun)	peeress (noun)
a noblewoman ranking below a duchess and above a countess	a woman of the peerage in Britain
the wife or widow of a marquis