superorder vs taxonomic group

superorder and taxonomic group both are nouns.

Word	Noun	Adjective	Verb	Adverb
superorder	Yes	No	No	No
taxonomic group	Yes	No	No	No

As nouns, taxonomic group is a hypernym of superorder; that is, taxonomic group is a word with a broader meaning than superorder:

superorder: (biology) a taxonomic group ranking above an order and below a class or subclass
taxonomic group: animal or plant group having natural relations

Other hypernyms of superorder include taxon, taxonomic category.

superorder (noun)	taxonomic group (noun)
(biology) a taxonomic group ranking above an order and below a class or subclass	animal or plant group having natural relations