mettle vs courage

mettle and courage both are nouns.

Word	Noun	Adjective	Verb	Adverb
mettle	Yes	No	No	No
courage	Yes	No	No	No

As nouns, courage is a hypernym of mettle; that is, courage is a word with a broader meaning than mettle:

mettle: the courage to carry on
courage: a quality of spirit that enables you to face danger or pain without showing fear

Other hypernyms of mettle include braveness, bravery, courageousness.

mettle (noun)	courage (noun)
the courage to carry on	a quality of spirit that enables you to face danger or pain without showing fear