accent mark vs grave

accent mark and grave both are nouns.

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

As nouns, grave is a hyponym of accent mark; that is, grave is a word with a more specific, narrower meaning than accent mark:

accent mark: a diacritical mark used to indicate stress or placed above a vowel to indicate a special pronunciation
grave: a mark (`) placed above a vowel to indicate pronunciation

Other hyponyms of accent mark include stress mark, acute, acute accent, ague, grave accent, double acute accent, Hungarumlaut.

accent mark (noun)	grave (noun)
a diacritical mark used to indicate stress or placed above a vowel to indicate a special pronunciation	a place for the burial of a corpse (especially beneath the ground and marked by a tombstone)
	a mark (`) placed above a vowel to indicate pronunciation
	death of a person

accent mark (adjective)	grave (adjective)
	causing fear or anxiety by threatening great harm
	of great gravity or crucial import; requiring serious thought
	dignified and somber in manner or character and committed to keeping promises

accent mark (verb)	grave (verb)
	carve, cut, or etch into a material or surface
	shape (a material like stone or wood) by whittling away at it