This is the 10054th most frequent Polish word.
bestsellerowej
"Relating to a bestseller."
The word 'bestsellerowej' is used as an adjective that modifies 'autorki,' indicating the author is associated with a bestseller.
Czytałem książkę bestsellerowej autorki.
I read the book of a bestselling author.
Here, 'bestsellerowej' describes 'powieści,' marking it as a novel that achieved bestseller status.
Fabuła bestsellerowej powieści była niezwykle wciągająca.
The plot of the bestselling novel was extremely captivating.
In this sentence, 'bestsellerowej' qualifies 'serii,' making it clear that the series is recognized as a bestseller.