Originally a theory of society. As the name of a political or economic theory which rests upon the abolition of the right of private property, especially the means of production and distribution, and seeks the overthrow of capitalism by revolutions, it is attested from 1850, a translation of German Kommunismus (itself from French), in Marx and Engels' "Manifesto of the Communist Party." Compare communist.
By 1919 and through and mid-20c. it was a general a term of abuse for revolutionaries, implying anti-social criminality without regard to political theory.
Each [i.e. socialism, communism, anarchism] stands for a state of things, or a striving after it, that differs much from that which we know; & for many of us, especially those who are comfortably at home in the world as it is, they have consequently come to be the positive, comparative, & superlative, distinguished not in kind but in degree only, of the terms of abuse applicable to those who would disturb our peace. [Fowler]