synarchy
Concise Oxford English Dictionary © 2008 Oxford University Press:
synarchy /ˈsɪnɑːki/
▶noun joint rule or government by two or more individuals or parties.
– derivatives
synarchic adjective,
synarchist noun.
synarchic adjective,
synarchist noun.
– origin C18: from Gk sunarkhia, from sunarkhein ‘rule jointly’.
'synarchy' also found in these Oxford entries:

