The GUTHALUS is mentioned by Pliny in his Historia Naturalis (IV,100)
as a river flowing into the Baltic. It has sometimes been identified
as the Oder. Some suggest that the "GUT" refers to the Goths. I'm
wondering if an alternative etymology might be possible, viz., where
GUTHALUS might mean something like "good (sea)neck" in Old Germanic.
What do you think Piotr?