The problem with word definitions in politics is that people tend to interpret them vastly different. A word has the meaning people give to it. So people often try to change and shift the definitions of words to repurpose them as it fits their agenda. That means for many political ideologies there are different, often contradicting, definitions.
The Merriam Webster dictionary defines Socialism as this:
Simple Definition of socialism
a way of organizing a society in which major industries are owned and controlled by the government rather than by individual people and companies
Full Definition of socialism
any of various economic and political theories advocating collective or governmental ownership and administration of the means of production and distribution of goods
- a: system of society or group living in which there is no private property,
- b: a system or condition of society in which the means of production are owned and controlled by the state
a stage of society in Marxist theory transitional between capitalism and communism and distinguished by unequal distribution of goods and pay according to work done
As you can see these are four different ways to define socialism which are partially overlapping and partially contradicting. Let's see how they fitted the Soviet Union.
Simple definition: way of organizing a society in which major industries are owned and controlled by the government rather than by individual people and companies
Applies. Most industry in the USSR was state-owned.
1: any of various economic and political theories advocating collective or governmental ownership and administration of the means of production and distribution of goods
Collective? Not really. The USSR collectivized the agriculture sector quite a lot in the 30s, but in practice it just increased government control and reduced the self-determination rights of the farmers instead of improving them. Government ownership? Applies to most other industries, as explained in the last point.
2a: system of society or group living in which there is no private property
There was private property in the Soviet Union, but there were regulations about what could and could not be owned by private people. Such restrictions usually exist in any country, but while most non-socialist countries mostly ban the possession of certain items for safety reasons (weapons, drugs, hazardous chemicals...), the USSR also did it for property because it had economical value (housing, factories, farmland...).
2b: a system or condition of society in which the means of production are owned and controlled by the state
This is a stronger form of the simple definition and the definition 1. Mostly applies. Most means of production were controlled by the state, but not all of them.
- a stage of society in Marxist theory transitional between capitalism and communism and distinguished by unequal distribution of goods and pay according to work done
There definitely was an unequal distribution of goods and pay. One could argue that the totalitarian Soviet Union regime was a necessary step on the road to true Communism which was never completed. But because the Soviet Union doesn't exist anymore, we can only speculate if the Soviet Union would have ever transited to Communism if it had the chance or if it would have developed in a different direction.
Summary: The Soviet Union was socialist according to most of the possible interpretations of the term.
Socialism always meant that workers control their workplace.
The system you are talking about here is often referred to as Syndicalism. And the variant of it which "doesn't need a government at all" is called Anarcho-Syndicalism.
