Polyxô (Πολυξω) is a name shared by two of the Okeanides and according to some sources the Hyades. In addition to the six Okeanids there are records that state that before being placed in the Hyades. also helped rear. There is some confusion as towards whether Polyxo (Okeanid) helped rear Dionysius or if it was. Either way her name means "of the thick woods." Based on her name one would venture a guess that she was an Okeanid of a stream of river which would mean she would be one of the Potameides (Naiad) since streans are sometimes found in the woods
Okeanos & Tethys
"from Oceanus and Tethys [were born] the Oceanides--namely yaea, Melite, Ianthe, Admete, Stilbo, Pasiphae, Polyxo, Eurynome, Euagoreis, Rhodope, lyris, Clytia, Teschinoeno, Clitenneste, Metis, Menippe, Argia."
Hyginus, Fabulae, 1-49