This is the 2413th most frequent Polish word.
ścianie
"Ścianie" means "wall" in the locative case in Polish.
The word 'ścianie' is used here in the locative case to indicate the location where the picture is hanging.
Obraz wisi na ścianie.
The picture is hanging on the wall.
The word 'ścianny' is used in the genitive case to describe proximity, indicating possession or context relating to the wall.
Mieszkam blisko tej ściany.
I live close to this wall.
Here, 'ścianie' is also in the locative case, used after the preposition 'w' to show inclusion or involvement within.