So what have we learned today? The same word can have multiple and rather vastly different meanings depending on your geographic location and historical understanding.
No, "communism" isn't a subjective term. Some people just use it wrong and/or haven't bothered to really find out what it means.
Sorry, I was thinking more along the lines of liberalism, socialism, anarchyism? (is that a word? I don't think so...). Hat tips to the prior discussion involving communism, although I'd probably still try to jump in the ring on stolfi's side as my thinking was similarly misplaced :/