Genealogy / THE MEANING AND RESEARCH OF MY POLISH LAST NAME, SURNAME? [4500]

Merged: The surname Glinka.

My grandfather from Ostrołęka is named "Glinka." I've done a bit of research on it, and all the people I found in history with that name were Russian. But my grandfather says that he doesn't have a drop of Russian blood. Does anybody happen to know where the name "Glinka" comes from? Thanks!