Definition of sebastia:
(n) :
A village in Nablus Governorate, West Bank, Palestine; the former capital of the Kingdom of Israel; formerly, Samaria (archeological site).
(n) :
(historical) Former name of Sivas: a municipality, the capital of Sivas district and Sivas Province, Turkey.
(n) :
(historical) A theme of the Byzantine Empire centered on Sivas.