The way it is used in mainstream political discourse, it holds no substantive meaning. “Communism” as used since the 1950s to describe various countries around the world (from Nicaragua to Cuba to to Vietnam) is just a term referring to polities that the US business state does not perceives as refusing to integrate in the US-dominated world economic system. Eisenhower used to be quite frank about this (we need their tungsten, etc.).
It might be claimed that a state is “communist” when its economy is partly nationalized (under control of state planning). However, the criterion of nationalized industry does not correlate at all in actual political discourse with the label “communism.” Chile, considered a leader of the free-market world–since the US helped take it over from the Allende govt and restructured its economy–has had the central parts of its economy nationalized for decades (i.e., the copper industry). Many nationalist leaders, from Ho Chi Minh to the early anti-Baptista Castro to Nicaraguan and Guatemalan peasants and Indians were blanket labelled “communists,” even when they had no further aspirations than the democratic sovereignty of their country.
Returning to the notion of market economy vs. state-planned economy, the US, it turns out, has substantial sectors of its economy managed by the state, from the Pentagon’s entire budget to the industry targets, tariffs and subsidies, R&D, bank bailouts, international trade agreements, and so on. If you’ve used computers, radios, enjoyed the photos of Neil Armstrong planting a flag on the moon, used the internet, or flown in an airplane, you’ve appreciated the fruits of state-directed enterprise within the US state-capitalist system. These were not products of the market; they came out of the state sector, which had developed them over decades, and were then handed over to the market for commodity refinement–but only after the state had produced the basic technology and produced a profitable commodity.
Chomsky drives the point home succinctly in this video: