What are the necessary and sufficient conditions for an economic system (or mode of production) to be classified as "Capitalism"?
Is it markets? Is it for-profit corporations? Is it limited liability companies? Is it workers selling their labour to capitalists/employees? Is it freedom to set up companies? Is it a low degree of government productive activity? Is it a subset of these or other elements?
I imagine the answer would depend on a particular schools of thought, so in principle I would expect different answers.
Disclaimer 1: this question is not requesting opinions about what capitalism is, it is not, it should be, it should be not, but authoritative answers, with proper references.
Disclaimer 2: for those voting to close this as too-broad, I asked on meta whether this question was on-topic, and (albeit not a popular post) it seems people agreed it was.