Where does “płotnicka” come from?

płotnicka (Polish) comes from Vilamovian płoc, from Latin placenta, from Ancient Greek πλακόεντα, from Ancient Greek πλακοῦς, from Ancient Greek πλακόεις, from Ancient Greek πλάξ, from Proto-Hellenic pləks, from Proto-Indo-European pleh₂- — flat.