matte

nouns

a mixture of sulfides that forms when sulfide metal ores are smelted
is a type of (narrower)
(chemistry) a substance consisting of two or more substances mixed together (not in fixed proportions and not with chemical bonding)
the property of having little or no contrast; lacking highlights or gloss

verbs

change texture so as to become matted and felt-like
"The fabric felted up after several washes"

adjectives

not reflecting light; not glossy
"flat wall paint"; "a photograph with a matte finish"