covered smut vs smut fungus

covered smut and smut fungus both are nouns.

Word	Noun	Adjective	Verb	Adverb
covered smut	Yes	No	No	No
smut fungus	Yes	No	No	No

As nouns, smut fungus is a hypernym of covered smut; that is, smut fungus is a word with a broader meaning than covered smut:

covered smut: a smut fungus causing a smut disease of grains in which the spore masses are covered or held together by the grain membranes
smut fungus: any fungus of the order Ustilaginales

Other hypernyms of covered smut include smut.

covered smut (noun)	smut fungus (noun)
a smut fungus causing a smut disease of grains in which the spore masses are covered or held together by the grain membranes	any fungus of the order Ustilaginales