Mrs
I don't like Tarquin. But I met adorable baby named Torquil a few days ago... I personally like Torquil and Florian (I wonder if DH would veto Torquil. Hm...)
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Yes, Florianne is the feminine version. It sounds different in French, but probably (definitely?) not in English.
Because in French Florian sounds different than in English, but Florianne (in French) sounds very much like Florian (in English). Sorry, I don't think I'm making sense... (English is sometimes a difficult language. grumble)