Refers to a society where the majority of the wealth is controlled by an ever-shrinking minority; as such, the economic growth of that society becomes dependent on the fortunes of that same wealthy minority; economic growth is powered and consumed by the wealthiest upper class of society. (source: investopedia)
An economy that is very influenced by the very wealthy or the study of the production and distribution of wealth. (source: wiktionary)
Notably on: Michael Moore’s Capitalism: A Love Story (2009) referring to a Citigroup report dated from 2006 describing the pattern of growth in the US economy. As a matter of fact, apparently Citigroup analysts describe the whole world economy as a plutonomy. That surprised uh?