ˌ ̷ ̷ ̷ ̷ˈōnēəm noun
( plural panio·nia -ēə)
Usage: usually capitalized
Etymology: New Latin, singular of panionia, from Greek paniōnia, from pan- + Iōnia Ionia — more at ionian
: a gathering of all the Ionians held on Mycale at which Poseidon was worshiped and political matters were discussed