LSJ
ὁ, enslavement, ἅπτεσθαι or ἐφάπτεσθαί τινος ἐπὶ καταδουλισμῷ, GDI 1685.5, 1686.8, al. (Delph.).
Liddell-Scott-Jones, Greek-English Lexicon (9th ed., 1940)
Pape
ὁ, = καταδούλωσις, Inscr., oft.
Pape, Griechisch-deutsches Handwörterbuch (3. Aufl., 1914)