Henrik Theiling wrote:
> Would you happen to know until when the term 'versipellis' was know to
> Romans or whether it was a Vulgar Latin word at all? 

As a compound it would understood by Romans as "skin-changer" - but 
whether it had any currency in colloquial use is rather doubtful.

> The dictionaries say it is used by Plautus, 

Plautus used it as an epithet of Jupiter. Later writers Pliny, Petronius 
& Appuleius use it to mean "werewolf."

> but I have no clue how much it is used by
> ordinary people, too, and how long.  

As far as I know, there is no indication that the word was much used (if 
at all) in colloquial speech. The evidence of the Romancelangs is that 
the the word didn't make it into Vulgar Latin.

> Did it leave any trace in modern Romance?
Not that I am aware of.

> Elliot asked for the word and before that, I assumed Latin had none so
> I compounded 'man-worf' in Ţrjótrunn.  

All the modern Romancelangs have formed some sort of compound, whether 
of 'man' + 'wolf' as in Spanish _hombre lobo_ (Thinks: that is a counter 
example, isn't it?) or Portuguese _lobisomem_. Or an special epithet 
added to wolf to make it clear that it's one of those 'humanoid wolves', 
like French 'loup-garou' or Italian 'lupo mannaro'.

> But if it is used in Vulgar Latin, 

It wasn't - you're compound is likely, given the scenario of your language.

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Nid rhy hen neb i ddysgu.
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