phra·try 
(frātrē)
(frātrē)n. pl. phra·tries
1. A kinship group constituting an intermediate division in the primitive structure of the Hellenic tribe or phyle, consisting of several patrilinear clans, and surviving in classical times as a territorial subdivision in the political and military organization of the Athenian state.
2. Anthropology An exogamous subdivision of the tribe, constituting two or more related clans.
[Greek phrātriā, from phrātēr, phrātr-, fellow member of a clan; see bhrāter- in the Appendix of Indo-European roots.]
phratric adj.