Arsacid /ˈɑɹsəsɪd/adjective 2noun 1forms 2 adjective2 •(historical) Of or pertaining to the Parthian dynasty established by Arsaces I which ruled the Parthian Empire during 247 BC – 224 AD, Armenia during 54–428, as well as Iberia and Caucasian Albania •(historical) Of or pertaining to the realms ruled by that dynasty noun1 •(historical) A member of the Arsacid dynasty formsArsacidae · Arsacids