Communism is the goal of socialism. The original democratic socialists, people like Eduard Bernstein, called it that because the idea was that communism could be achieved through gradually reforming existing political systems. It became more and more obvious that this was just a pretense, with things like the betrayal of the Second International and the demsoc support of WWI, and now we’re at a point where the pretense is often dropped entirely.

It’s been used to oppress millions of people.

Communism has never been used to oppress anyone because it’s never existed as a system (not counting primitive communism). There have only been socialist states that claim to be working towards communism. The Union of Soviet Socialist Republics was not called The Union of Soviet Communist Republics.