Of course there are, every language has them. But no worry, when you're introduced to them it'll definitely be with sufficient non-verbal cues to recognize them as exceptionally crude.

I know, that the f-word is "fuck". But what are the c- and the n-word? Please do not write in riddles. And which are the other 4 words in American English?

@HubertSchölnast The C-Word is under the spoiler and the N-Word may be "negro" or similar. And I'm wondering about the other 3 American words (we know already that 1 of 4 is "toilet" for whatever reasons).

I agree this is quite a good question, and I think we have a couple of those words in German. However, it seems to me that in a conversation about the linguistic aspects of such words, the respective words would usually still be written or spoken out rather than masked with abbreviation-euphemisms (like 'f-word'). Rather than a difference in severity of the German expressions, that may also be a result of the cultural difference with German being a "direct culture" and such, though.

@HubertSchölnast This is not a question about English, but about German, so these words do not matter here. If you would like to know these words in English please ask a question on english.stackexchange.com I'm asking for a list of unspeakable words in German, if there are any words like that...

@KilianFoth: It's only obvious to a native speaker, so no, I don't know...

@O.R.Mapper That's what I'm hoping for...

@Fabby True, this Q is not about English, but I think knowing the English N/F/C-words does matter here because it helps finding comparable expressions in German.

I think there is no such definitive list, because this is a matter of social situation and there a fluid boundaries, therefore the answer is opinion-based. Also the question itself is very "un-german". Using the words "unspeakable" and asking people to put the words in spoiler tags, imho comes across as childish and hysterical in the eyes of many Germans. These are just words after all and not a magical spell whose pronunciation will harm someone. So get ready to get dismissive answers or few answers at all, since this is a very "american" problem imho.

Yes, these words exist and sometimes they are used, but they are considered probably much more harmful as you would think! It is better if you don't even try to learn them!

Actually, it's not so much that "toilet" is offensive in American speech as that, in American speech the word refers not to the room but to the piece of plumbing on which one excretes into. So there is nothing untoward about saying over dinner "I had a new toilet installed in my bathroom yesterday." (Well, some might not like the whole topic, but the word isn't offensive.) Given that difference in meaning, "where is the toilet" sounds a little odd. However, it is still true that we Americans are a prudish bunch.

I think this question should be edited to remove the assumptions about a finite list of words to avoid in English. Why is cunt one of the big three words while wanker for instance isn't?

@PierreArlaud Why certain words have more weight than others is an interesting question but the fact that cunt has far more weight that wanker is a simple fact. English is my native language and I have no problem understanding which words are appropriate in which situations but in other languages I don't know whether a given 'bad' word is mild or extreme, whether it is acceptable in this context but not in that one. My advice would be to simply avoid them all, possibly forever.

In Britain, and in particular in certain parts of Britain, the C-word is not considered that offensive and is not gendered in use.

@Fabby: This is not a question about English, but about German, so these words do not matter here Why did you use them, then? Also, they are not unspeakable but very much speakable and the attempt to be P.li..lly Co...ct by trying to hide them is just silly.

It's all about the context. And apparently I took the right path as in German, there are no unspeakable words... @WoJ

@Fabby: the thing is that in English there are no unspeakable words either. This is just childish/silly to hide them as if they would shock someone (we are adults, and if my children read this it means they are old enough to suffer a "fuck" or a "negro" and start to understand when and how to use (or not use) them)

@WoJ think about that next time when one of your kids says to your face: "Je m'en branle..." :P :D

And even the most primitive persons are able to have a polite conversation, in which their values decide, what is polite and what is not. Language isn't the private property of the middle and upper class. In the US, by the way, this happens to be a fact too. And I have often observed black people calling each other the N-word - and it wasn't the milder one - regularly without irony or provocation. It is never a word by itself, which is offensive.