pythium vs fungus

pythium and fungus both are nouns.

Word	Noun	Adjective	Verb	Adverb
pythium	Yes	No	No	No
fungus	Yes	No	No	No

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

pythium: any fungus of the genus Pythium
fungus: an organism of the kingdom Fungi lacking chlorophyll and feeding on organic matter; ranging from unicellular or multicellular organisms to spore-bearing syncytia

pythium (noun)	fungus (noun)
any fungus of the genus Pythium	an organism of the kingdom Fungi lacking chlorophyll and feeding on organic matter; ranging from unicellular or multicellular organisms to spore-bearing syncytia