On eunoia.world you can find a list of words that don't translate to other languages, such as the German word "Backpfeifengesicht", which means "a face in need of a slap." Just refresh the web page to see a new set of words.
Here are some interesting ones:
Vybafnout is a Czech word that means "To jump out and say 'boo'"
Vellichor is an English word that means "the strange wistfulness of used bookshops"
Rabenmutter is the German word for "a bad mom"