This is the 9519th most frequent Polish word.
winnickiej
"Winnickiej" is the locative or genitive form of the Polish adjective "winnicki," which means "of or relating to Winnica," a place name.
In this sentence, 'winnickiej' is an adjective derived from 'Winnica,' the Polish name for the city of Vinnytsia, describing something related to this place, here referring to the author's origin.
Książki winnickiej autorki są bardzo inspirujące.
The books by the Vinnytsia-based author are very inspiring.
Here, 'winnickiej' functions as an adjective describing the café, indicating its location or connection with Vinnytsia.
Możemy spotkać się w winnickiej kawiarni jutro po południu.
We can meet at the Vinnytsia-based café tomorrow afternoon.
In this usage, 'winnickiej' is in its feminine singular nominative form and describes 'pieśni,' signifying songs originating or traditionally associated with Vinnytsia.