Hi
Anastasia,
Gylve is a modern form of the Old Norse name Gylfi (in Iceland still the old form is used). It comes from the Old Norse word "gjalf" meaning "sea, ocean".
It is a name of a Swedish king in the mythology.
The pronunciation is hard to describe...
YILL-veh
The y sounds like a mixture of a French i and u (or a
German i and ü)
Regards,
Satu