ὑπὲρ τῆς παροικίας τῶν καθ᾽ ἡμᾶς μερῶν.  On the use of παροικία in this sense, cf. Bp. Lightfoot, Ap. Fathers I. ii. 5.  So Apollon. in Eus., H.E. v. 18. ἡ ἱδία παροικία, of the Christian society.  Thus the meaning passes to parochia and parish.