dullness vs matt

dullness and matt both are nouns.

Word	Noun	Adjective	Verb	Adverb
dullness	Yes	No	No	No
matt	Yes	Yes	No	No

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

dullness: a lack of visual brightness
matt: the property of having little or no contrast; lacking highlights or gloss

Other hyponyms of dullness include dimness, subduedness, flatness, lusterlessness, lustrelessness, mat, matte.

dullness (noun)	matt (noun)
lack of sensibility	the property of having little or no contrast; lacking highlights or gloss
without sharpness or clearness of edge or point
the quality of lacking interestingness
a lack of visual brightness
the quality of being slow to understand

dullness (adjective)	matt (adjective)
	not reflecting light; not glossy