Someone is right on the internet

Deep in the comments thread of this LL post about "untranslatable" words (Schadenfreude, litost, and the like), John Cowan said:

No, none of these are untranslatable. The real untranslatable words are things like hottentottententententoonstelling 'Hottentot tent exhibition'. I mean, you can't just replace that word with its English gloss. You'd have to find something in English with similar impact, and where can you find that? Supercalifragilisticexpialidocious and ultramicroscopicosilicovolcanoconiosis just don't cut it.

Or you could go with hard, which cannot be translated into German because in a given context you need one of about 40 German adjectives, of which the only one I remember offhand is alkoholisch.