This is the 15877th most frequent Russian word.
промерзшая
Frozen through; thoroughly chilled.
The word 'промерзшая' is used as a modifier to describe the wall, indicating that it is frozen or deeply cold.
Я осторожно коснулся промерзшей стены, и почувствовал холод.
I carefully touched the frozen wall and felt its cold.
The word 'промерзший' describes the pie, emphasizing that it is fully frozen.
Этот промерзший пирог все еще можно съесть, просто нужно подождать, пока он разморозится.
This frozen pie can still be eaten; it's just necessary to wait for it to thaw.
The word 'промерзшая' is used to characterize the ground as being affected by cold to the point of freezing.