This is the 6592nd most frequent Polish word.
delkowską
"Delkowską" is the accusative or instrumental form of "Delkowska," a Polish surname.
The word 'delkowską' is used as an adjective describing the road's name, possibly referring to a road named Delkowska.
Piotr spacerował delkowską drogą w kierunku miasta.
Piotr walked along the Delkowska road towards the city.
Here, 'delkowskiej' modifies 'dolinie' (valley), inflected to match the feminine singular form of the noun it describes, connected to the location named Delkowska.
Widziałem piękną kapliczkę w delkowskiej dolinie.
I saw a beautiful chapel in the Delkowska valley.
In this sentence, 'Delkowska' is part of a proper noun describing a specific culture or tradition, indicating a historical or cultural aspect.