fogginess vs vagueness

fogginess and vagueness both are nouns.

Word	Noun	Adjective	Verb	Adverb
fogginess	Yes	No	No	No
vagueness	Yes	No	No	No

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

Other hyponyms of fogginess include dimness, faintness.

fogginess (noun)	vagueness (noun)
the quality of being indistinct and without sharp outlines	unclearness by virtue of being poorly expressed or not coherent in meaning
an atmosphere in which visibility is reduced because of a cloud of some substance	indistinctness of shape or character