high-mindedness vs grandeur

high-mindedness and grandeur both are nouns.

Word	Noun	Adjective	Verb	Adverb
high-mindedness	Yes	No	No	No
grandeur	Yes	No	No	No

As nouns, grandeur is a hypernym of high-mindedness; that is, grandeur is a word with a broader meaning than high-mindedness:

high-mindedness: elevated ideals or conduct; the quality of believing that ideals should be pursued
grandeur: the quality of elevation of mind and exaltation of character or ideals or conduct

Other hypernyms of high-mindedness include magnanimousness, nobility, nobleness.

high-mindedness (noun)	grandeur (noun)
elevated ideals or conduct; the quality of believing that ideals should be pursued	the quality of being magnificent or splendid or grand
	the quality of elevation of mind and exaltation of character or ideals or conduct