There are quite a few terms going around in the Anime fandom with many slightly different meanings, that one can provoke flamewars just by using one in the wrong context in the wrong crowd. So first of all, let’s clarify some words from my personal dictionary:
Otaku – “Anime fan” . Either that, or if you believe the friendly reminders of those posters who inevitably comment on every usage of the word, the original Japanese means “creepy perverted reculse who is obsessed with anime”, that is basically the same thing, but sprinkled with dysphemisms. I tend to prefer the first meaning, because to me, that doesn’t seem that much different from all the other labels like “geek” or “liberal/conservative”, or “gay”, or “bookworm”, that can also have an edge, but only if you say them that way. Besides, I also have the feeling that these helpful posters obtained their information from either Sankaku Complex, or Nogizaka Haruka no Himitsu, neither of which seems to be a more credible source than my own.
Weeaboo – “newbie anime fan”. It used to mean something like “blind anime fanboy and Japan worshipper”, but as far as I can tell, the phrase and the stereotype spread out so well, that anyone who was the member of the fandom for more than a few weeks, and intends to stay inside, is forced to drop any signs of obvious weeabooism, or get mercilessly mocked for it. In the recent years, the only people whom I saw genuinely declaring Japan to be “the best country ever”, or dropping random japanese words in their speech, were newbies who still didn’t get the memo that it’s not cool.
Slice-of-life- That one is supposed to be an universal genre, but anime fans still managed to tangle up their own take on it. The main schools are that it either means “anything that is not speculative fiction”, or “a specific presentation format, that entirely lacks intentional storytelling or dramatic rules”. I’m somewhere in-between these two, I believe that the main issue is whether or not the setting intentionally tries to appeal to drawing parallells with events of the average viewer’s life. So, for example I would say that Lucky Star has comedic timing and absurdities, it’s still a slice-of-life because of how it focuses on the mundane, like oversleeping and missing school, or the vending machine eating your money. But I don’t think that something Hanasaku Iroha is a slice-of-life, because there, detailing the protagonists’ unique life is in the spotlight.
Moe show– I try to avoid this one. If you mean the “K-on genre”, there are better terms like “schoolgirl series” or “girl-group series”, or maybe “four girl series” (Hmm… 4 girl… young girl… “- chan”… there is probably a pun in there somewhere). Or if you mean it in a more generic way, as in any show that has a cuteness appeal, then it’s a very meaningless phrase. Cuteness is Japan’s ideal of attractiveness, it’s self-evident that every show that is not super-artsy or grimdark for shock value, is trying to be more or less attractive to the audience. Using a genre name for them, is like using a genre name for every Hollywood movie that stars sexy actresses.
Tsundere– “A character who hides her affections behind hostility. Can be either a character development process, or comically swift mood-swinging.” Not included: The assumption that it’s always the same basic cliché character. Hermione Granger, Katherina Minola, Suzumiya Haruhi, and Horo all have Tsundere attitudes, the difference between them and the cardboard cutouts of generic anime isn’t that they use a different trope, but that the latters’ writers failed to add anything else to them. That’s bad writing.