polyzoa vs phylum

polyzoa and phylum both are nouns.

Word	Noun	Adjective	Verb	Adverb
polyzoa	Yes	No	No	No
phylum	Yes	No	No	No

As nouns, phylum is a hypernym of polyzoa; that is, phylum is a word with a broader meaning than polyzoa:

polyzoa: marine or freshwater animals that form colonies of zooids
phylum: (biology) the major taxonomic group of animals and plants; contains classes

polyzoa (noun)	phylum (noun)
marine or freshwater animals that form colonies of zooids	(biology) the major taxonomic group of animals and plants; contains classes
	(linguistics) a large group of languages that are historically related