The definition of a plutocracy is a political system where the wealthy govern.(noun)
When the richest people have all of the power in a society and make all of the political decisions, this is an example of a plutocracy.
See plutocracy in Webster's New World College Dictionary
noun pl. plutocracies
Origin: Gr ploutokratia < ploutos, wealth, akin to plein, to float, swim (< IE base *pel- > full) + kratein, to rule
See plutocracy in American Heritage Dictionary 4
noun pl. plu·toc·ra·cies
Origin: Greek ploutokratiā
Origin: : ploutos, wealth; see pleu- in Indo-European roots
Origin: + -kratiā, -cracy.
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