Translating nicknames

[Azande]

A couple of short stories I am working on are set in my native city in Italy, Torino and I have a recurrent character which is only known by his nickname - Grigio, which means Grey in English.
My question is, should I keep the Italian version or use the English one (considering that I do write in English and not Italian)?

[escritora]

I'd keep the Italian version.

[Matera the Mad]

I'd go with the Italian too, it's harmonious with the setting.

[Wayne K]

I'd keep it Italian too. The only Grey I've ever known was a horse.

[john barnes on toast]

Definitely go with the Italian.

And even if the nickname is determined by a physical characteristic, you shouldn't feel any need to labour it.
A line like: 'He was called Grigio, on account of the colour of his hair.' isn't reliant on people knowing what grigio means. Most people will work it out, or even look it up, and will have learned something. Those that don't aren't worth worrying about.
Credit your audience with some intelligence.

[Wayne K]

Definitely go with the Italian.

And even if the nickname is determined by a physical characteristic, you shouldn't feel any need to labour it.
A line like: 'He was called Grigio, on account of the colour of his hair.' isn't reliant on people knowing what grigio means. Most people will work it out, or even look it up, and will have learned something. Those that don't aren't worth worrying about.
Credit your audience with some intelligence.
I told the librarian here that if I come across a word I don't know in a book, I look it up, and she looked at me like I was from Mars.

[Azande]

Thanks for the advice, Grigio will be.

[mlazzer]

I would keep the Italian name and if it's really important that the reader knows it means "grey" then you can explain it in a different way. But stick with the real name.