fuzziness vs opacity

fuzziness and opacity both are nouns.

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

As nouns, opacity is a hypernym of fuzziness; that is, opacity is a word with a broader meaning than fuzziness:

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

Other hypernyms of fuzziness include opaqueness.

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