fug vs murkiness

fug and murkiness both are nouns.

Word	Noun	Adjective	Verb	Adverb
fug	Yes	No	No	No
murkiness	Yes	No	No	No

As nouns, murkiness is a hypernym of fug; that is, murkiness is a word with a broader meaning than fug:

fug: (British informal) an airless smoky smelly atmosphere
murkiness: an atmosphere in which visibility is reduced because of a cloud of some substance

Other hypernyms of fug include fog, fogginess, murk.

fug (noun)	murkiness (noun)
(British informal) an airless smoky smelly atmosphere	the quality of being cloudy
	an atmosphere in which visibility is reduced because of a cloud of some substance