The Collaborative International Dictionary
Plutarchy
Plutarchy \Plu"tar*chy\, n. [Gr. ? wealth + -archy.] Plutocracy; the rule of wealth. [R.]
Douglas Harper's Etymology Dictionary
plutarchy
"plutocracy," 1640s, from Greek ploutos "wealth" (see Pluto) + -archy.
Wiktionary
plutarchy
n. rule by the wealthy; plutocracy