LSJ
(on the accent v. Hdn. Gr. 1.229), Ion. ἀρχιητρός, ὁ, court or official physician, OGI 256.5 (Delos, ii/i BC), etc. ; of the Roman Emperors, Gal. 14.2, al. ; of communities, arch. populares Cod. Theod. 13.3, Cod.Just. 10.52.10, al. ; generally, responsible practitioner, Aret. CA 2.5; cf. ἀρχιΐατρος.
Liddell-Scott-Jones, Greek-English Lexicon (9th ed., 1940)
Pape
[ιᾱ], ὁ, erster Leibarzt, Sp.
Pape, Griechisch-deutsches Handwörterbuch (3. Aufl., 1914)