Lexical Definition

‎ἐπαρχία‎ eparchía (ep-ar-khee'-ah) province ^G:N-F
from a compound of ‎ἐπί‎ and ‎ἄρχω‎ (meaning a governor of a district, "eparch")

province.

• a special region of government, i.e. a Roman præfecture

Abbott-Smith

† ἐπαρχεία (Rec. -χία, v. Bl., § 3, 5), -ας, ἡ (< ἔπαρχος, a prefect), [in LXX: Es 4:11 (מְדִינָה), Jth 3:6 A* ;]
the jurisdiction of a prefect, a province: Ac 23:34 25:1.†

*† ἐπάρχείος (Rec. -ον , of a prefect: ἡ ἐ. (sc. ἐξουσία) = ἐπαρχεια, q.v., Ac 25:1 (WH, mg.).†

Abbott-Smith References

Liddell-Scott-Jones

ἐπαρχία-ία, ἡ,

the government of an ἔπαρχος, or the district governed by him, = Latin provincia, [NT+2nd c.BC+]; of Carthage, empire, [Refs 2nd c.AD+]

__II military 'command', force occupying a district, [Refs 3rd c.BC+]

_{LSJ Scripture Refs: Acts.23.34}