stemma vs phratry

stemma and phratry both are nouns.

Word	Noun	Adjective	Verb	Adverb
stemma	Yes	No	No	No
phratry	Yes	No	No	No

As nouns, phratry is a hyponym of stemma; that is, phratry is a word with a more specific, narrower meaning than stemma:

Other hyponyms of stemma include family, family line, folk, kinfolk, kinsfolk, sept, side, breed line.

stemma (noun)	phratry (noun)
an eye having a single lens	people descended from a common ancestor
the hereditary derivation of an individual
a tree diagram showing a reconstruction of the transmission of manuscripts of a literary work