> Socialism: a political philosophy and movement encompassing a wide range of economic and social systems, which are characterised by social ownership of the means of production, as opposed to private ownership.

That is the meaning, it's not meaningless. It becomes meaningless when people just accept that it can mean anything they want, it can't. Socialism has a very specific characteristic: social ownership of the means of production.

If people misuse the term they need to be corrected. At least until the meaning completely shifts to something else, like what Americans try to do with the term "liberal" which does not, at all, mean "progressive" as is the usage in the USA.