Here is the Google dictionary's definition of social justice:
Justice in terms of the distribution of wealth, opportunities, and privileges within a society. "Distribution of wealth" is a phrase that has no part in any serious discussion of justice. Distribution of wealth is up to those who produce it. Then there's this, a typical bromide heard in social justice circles:
"Individuality gives way to the struggle for social justice"
"Individuality gives way to the struggle for social justice?". Excuse me, comrade? Then who acts? Whose struggle? Whose justice? Why should individuality give way?
Communists do not like to be specific when engaging in rhetoric or polemics. They prefer to intimidate you into becoming a true believer. That is the case with the null term "social justice", null, because it means nothing specific, relative to justice (in fact, it has nothing to do with justice at all). It carries a certain amount of clout, however. Everyone on the Left gives it lip service; it seems to be a noble goal, and besides, to argue against it would be like arguing against world peace, or puppies and kittens. There are problems here with specificity: who belongs to society? Answer: no one individual, and everyone in general (except yourself). If social justice pertained to individuals, then we all could lay a claim, based on justice, to a mansion in Bel Air. Or perhaps we could just lie around all day, smoking weed, and demand a house, electricity, food, clothing, and free Internet-in the name of "social" justice. What is just, who decides, and who passes out the goodies? And again, who is society? Everyone, except individuals? No, the collectivist answer is: the sum total of all the useful idiots, brainwashed automatons, and imprisoned captives who all believe, or pretend to believe, in the State as the benefactor of mankind.