At that time in Europe "socialism" basically just meant "good". It was a stand in for a government where you care about each other.

Then there's the more "theoretical" definition of socialism. In the US it might seem bewildering why Orwell considered the anarchists of that war to be the "true socialists" (despite Orwell being a communist, he had a lot of support for them). But the truth is that both anarchism and communism far pretty well within the boundaries of socialist theory historically. And that's quite evident when you think about the fact that the final goal of both of these theories is a stateless society