Faktycznie, Polin kojarzy się z Polis.
Ale też... hmmm... z Wikipedii wyczytałem, że to hebrajskie określenie na "Polskę":

Some Jewish historians say the Hebrew word for 'Poland' is pronounced as Polania or Polin in Hebrew. As transliterated into Hebrew, these names for Poland were interpreted as "good omens" because Polania can be broken down into three Hebrew words: po ("here"), lan ("dwells"), ya ("God"), and Polin into two words of: po ("here") lin ("[you should] dwell"). The "message" was that Poland was meant to be a good place for the Jews. In later centuries up to 80% of the Jewish world population lived in Poland.