phylum vs social group

phylum and social group both are nouns.

Word	Noun	Adjective	Verb	Adverb
phylum	Yes	No	No	No
social group	Yes	No	No	No

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

phylum: (linguistics) a large group of languages that are historically related
social group: people sharing some social relation

phylum (noun)	social group (noun)
(biology) the major taxonomic group of animals and plants; contains classes	people sharing some social relation
(linguistics) a large group of languages that are historically related