LSJ
α, ον, of or for admission; ἐ. οἶκοι rooms where the athletes were examined before they were admitted as candidates, IG 4.203.12 (Corinth, ii AD).
Liddell-Scott-Jones, Greek-English Lexicon (9th ed., 1940)
Pape
οἶκοι, Gemächer, wo die Wettkämpfer vor dem Kampfe untersucht wurden, Inscr. I p. 573.12.
Pape, Griechisch-deutsches Handwörterbuch (3. Aufl., 1914)