maharani vs princess

maharani and princess both are nouns.

Word	Noun	Adjective	Verb	Adverb
maharani	Yes	No	No	No
princess	Yes	No	No	No

As nouns, princess is a hypernym of maharani; that is, princess is a word with a broader meaning than maharani:

maharani: a great rani; a princess in India or the wife of a maharaja
princess: a female member of a royal family other than the queen (especially the daughter of a sovereign)

maharani (noun)	princess (noun)
a great rani; a princess in India or the wife of a maharaja	a female member of a royal family other than the queen (especially the daughter of a sovereign)