[ plu:'tɒkrəsi ]
■ noun ( plural plutocracies ) government by the wealthy.
↘a state or society governed in this way.
↘an elite or ruling class whose power derives from their wealth.
Derivatives
plutocratic adjective
plutocratically adverb
Origin
C17: from Gk ploutokratia , from ploutos 'wealth' + kratos 'strength, authority'.