opaqueness vs muddiness

opaqueness and muddiness both are nouns.

Word	Noun	Adjective	Verb	Adverb
opaqueness	Yes	No	No	No
muddiness	Yes	No	No	No

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

opaqueness: the quality of being opaque to a degree; the degree to which something reduces the passage of light
muddiness: the quality of being cloudy

Other hyponyms of opaqueness include cloudiness, murkiness, blurriness, fogginess, fuzziness, indistinctness, softness.

opaqueness (noun)	muddiness (noun)
the quality of being opaque to a degree; the degree to which something reduces the passage of light	the quality of being cloudy
incomprehensibility resulting from obscurity of meaning	a mental state characterized by a lack of clear and orderly thought and behavior
	the wetness of ground that is covered or soaked with water