Economic system based on private ownership
Capitalism is an economic system based on the private ownership of the means of production and their operation for profit. Central characteristics of capitalism include capital accumulation, competitive markets, price systems, private property, recognition of property rights, self-interest, economic freedom, meritocracy, work ethic, consumer...
I think most anti-capitalists, while correctly identifying problems in society resulting from capitalism, either fail to address how their desired alternative would actually fix said problems, or have a desired alternative with problems that vastly outweigh those of capitalism.