An economy or market with no regulation or restrictions on how the said market operates, thus allowing the most efficient allocation of a resources in an economy. The laissez-faire or 'market system' is the unplanned capitalist economic system. The extreme opposite is N.Korea, Cuba, China etc.
The 'passive' approach, or that of non-intervention to Macroeconomic management (as stated by harry flashman) is just one feature of the laissez-faire or market system.
Pierre, an economic adviser to the finance minister was going to propose a laissez-faire approach to the recession but was such a laissez-faire that he never got around to it.
A laissez-faire state can be solved with a metastatic voting system (metavote) or a system in which blockchain mutual credit is employed to cast a ballot.