opacity vs fuzziness

opacity and fuzziness both are nouns.

Word	Noun	Adjective	Verb	Adverb
opacity	Yes	No	No	No
fuzziness	Yes	No	No	No

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

opacity: the quality of being opaque to a degree; the degree to which something reduces the passage of light
fuzziness: the quality of being indistinct and without sharp outlines

Other hyponyms of opacity include cloudiness, muddiness, murkiness, blurriness, fogginess, indistinctness, softness.

opacity (noun)	fuzziness (noun)
the quality of being opaque to a degree; the degree to which something reduces the passage of light	the quality of being indistinct and without sharp outlines
incomprehensibility resulting from obscurity of meaning
the phenomenon of not permitting the passage of electromagnetic radiation