ague vs accent mark

ague and accent mark both are nouns.

Word	Noun	Adjective	Verb	Adverb
ague	Yes	No	No	No
accent mark	Yes	No	No	No

As nouns, accent mark is a hypernym of ague; that is, accent mark is a word with a broader meaning than ague:

ague: a mark placed above a vowel to indicate pronunciation
accent mark: a diacritical mark used to indicate stress or placed above a vowel to indicate a special pronunciation

Other hypernyms of ague include accent.

ague (noun)	accent mark (noun)
a mark placed above a vowel to indicate pronunciation	a diacritical mark used to indicate stress or placed above a vowel to indicate a special pronunciation
a fit of shivering or shaking
successive stages of chills and fever that is a symptom of malaria