diacritic vs accent

diacritic and accent both are nouns.

Word	Noun	Adjective	Verb	Adverb
diacritic	Yes	Yes	No	No
accent	Yes	No	Yes	No

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

diacritic: a mark added to a letter to indicate a special pronunciation
accent: a diacritical mark used to indicate stress or placed above a vowel to indicate a special pronunciation

Other hyponyms of diacritic include accent mark, breve, cedilla, circumflex, hacek, wedge, macron, tilde, umlaut, diaeresis, dieresis.

diacritic (noun)	accent (noun)
a mark added to a letter to indicate a special pronunciation	the relative prominence of a syllable or musical note (especially with regard to stress or pitch)
	distinctive manner of oral expression
	a diacritical mark used to indicate stress or placed above a vowel to indicate a special pronunciation
	the usage or vocabulary that is characteristic of a specific group of people
	special importance or significance

diacritic (adjective)	accent (adjective)
capable of distinguishing

diacritic (verb)	accent (verb)
	put stress on; utter with an accent
	to stress, single out as important