> I wasn't speaking French, I was speaking English, in which virgule means slash.

It seems like you and GP both have valid points.

Borrow-words usually (AFAIK) generally have the same meaning in the donor and recipient languages. So referring to the donor-language definition is a good way to figure out intended usage.

IIUC, virgule has different meanings in Latin, French, and English. I'm guessing that's what's throwing us off.