This is the 7075th most frequent Polish word.
holenderskich
"Holenderskich" means "Dutch" (adjective, plural or genitive form).
The word 'holenderskich' serves as an adjective, modifying 'malarzy' (painters), specifying their nationality or origin.
Kupiłem książki o historii holenderskich malarzy.
I bought books about the history of Dutch painters.
Here, 'holenderskich' modifies 'ulicach' (streets), indicating the origin or style associated with the Netherlands.
Podziwiałem architekturę na holenderskich ulicach.
I admired the architecture on Dutch streets.
In this sentence, 'holenderskich' modifies 'regionów' (regions), referring to their geographical location related to the Netherlands.