[Classical Latin] was the only language in which it was possible to hold an intellectual discussion, as the vernacular languages of the time lacked adequate vocabulary.
Alessandro Barbero, Charlemagne
Language teachers and translators know that there are words that present a real problem when an equivalent has to be found in another language. This is not (usually) because the concept does not exist but because what is perceived as one idea in one language is divided into many smaller concepts in another or is expressed by a circumlocution. The main exception of course is to be found in cultural or natural phenomena that exist in one language area but not in the other. In these cases the word is usually taken over directly: tundra, vodka, matador, canyon and veldt would be examples of this in English.
I know that Geoff Pullum says: Whenever you hear someone starting to say something that begins with "The X have no word for Y", or "The X have N different words for Y", never listen to them, and always check your wallet to make sure it's still there.
He is right to the extent that he is talking in terms of theoretical linguistics. In this series of posts I am looking at the practical difficulties faced by teachers and translators who are constantly having to find equivalent expressions in different languages in order to facilitate learning or understanding.