What's in a name?

All being well, we will set off for France  in a couple of weeks. One important bit of admin before we enter the canal system in Rouen is to obtain a Vignette giving permission to use the inland waterways. You can register the boat and order the Vignette online www.vnf.fr in four languages: French (obviously), English, German and Dutch.

So far so good.

The first part is bog standard, name, address, other contact details. Then,  the boat details. The first field is headed 'Currency', with an asterisk denoting that this is a compulsory field. I put a £ sign. Then I thought about it as it didn't make much sense. Was it a mistranslation? I tried translating the German and Dutch words and they too came up as 'currency'.

By now I was fed up but carried on to the next page. On here the same field is 'Name (currency)'.  Logically it would make more sense to put the boat name on the vignette wouldn't it? I asked Igor for his opinion as he knows about linguistics.

It turns out that the word on the French version of the page, 'devise', is most often translated to 'currency' but, in the marine context 'devise de bateau' means 'boat motto' or boat name.  It's really no more confusing than the fact that sheets on a boat are actually ropes, but why couldn't they just use the word 'Nom' if they knew it was going to be machine translated?