Portmanteau of plutocracy (rule of the wealthy) and oligarchy (rule of the few). Rule of the wealthy few. plutoligarchs have a lot of political influence and can get the legislature to legislate laws for their benefit. They also usually spend a massive amount of money on advertisements the like to influence the opinions of commonfolk. In these kinds of governments, the rich get richer and the poor get poorer. Plutoligarchy can cross from corporatism (aka capitalism) to communism.
America is a plutoligarchy. China is a plutoligarchy. Cuba is a plutoligarchy. The UK is a plutoligarchy. Most countries, if not all, are ruled by a small amount of people with lots of dough.