Capitalism
Capitalism is an economic system centered on the generation of profit by accumulating privately owned capital.
The locus of power in a capitalist system are the classes that manage to accumulate capital through several cycles of reinvesting the profits obtained from this same capital. This means that simply owning capital is not a definining property of the capitalist, because the inability to accumulate it signals capital only provides enough for their own subsistence and the continuation of their business.
When profits are sufficient to reinvest indefinitely, accumulation grows so large that subsistence is beyond guaranteed and excess can be used to wield influence and control the system.