subphylum Tunicata vs phylum

subphylum Tunicata and phylum both are nouns.

Word	Noun	Adjective	Verb	Adverb
subphylum Tunicata	Yes	No	No	No
phylum	Yes	No	No	No

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

subphylum Tunicata: tunicates
phylum: (biology) the major taxonomic group of animals and plants; contains classes

subphylum Tunicata (noun)	phylum (noun)
tunicates	(biology) the major taxonomic group of animals and plants; contains classes
	(linguistics) a large group of languages that are historically related