φράτριον

α, ον, τό
A. of or belonging to a φράτρα, at Athens, epith. of Zeus and Athena, as tutelary deities of the phratriae, Pl. Euthd. 302d; Ζεὺς φ. D. 43.14, IG 22.1237.1, prob. for Φρατόριος in Cratin.Jun. 9.5; also at Syros, IG 12(5).669; Ποτειδὰν ὁ φ. Schwyzer 323 B 14 (Delph., iv B. C.); οἱ θεοὶ οἱ φρήτριοι IG 14.759 (Naples), Röm.Mitt. 27.303 (Aquila).
II. φράτριον, τό, a temple of these deities, or any shrine used by the φρατρία, St.Byz. s.v. φρατρία, Poll. 3.52 codd.
III. φράτριος μήν,ὁ, name of month at Cyme, IGRom. 4.1302.54 (i B. C. /i A. D.).
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
An open-access project