1837, from French socialisme (1832) or formed in English (based on socialist) from social, adj. + -ism. Perhaps first in reference to Robert Owen's communes. "Pierre Leroux (1797-1871), idealistic social reformer and Saint-Simonian publicist, expressly claims to be the originator of the word socialisme" [Klein, also see OED discussion]. The word begins to be used in French in the modern sense c.1835.