What I wanted to say is "realsocialist" a la former Soviet Union or East Germany. I think part of the confusion is that I live in Germany, where socialist always means that kind of one-party authoritarian system. By this definition, e.g. Bernie Sanders would be a (left-wing) social democrat, but not a socialist.
I know for example in France, the middle-left-wing party calls themselves socialist... I believe they are slightly left of what you'd call "liberal" in the US.