This is the 17266th most frequent Polish word.
zakupiony
"Zakupiony" means "purchased" in English.
This sentence uses the past passive participle 'zakupiony' to describe something that has been bought, focusing on the action of purchasing as the product is now owned.
Produkt został zakupiony w sklepie internetowym.
The product was purchased in an online store.
Here, 'zakupionym' modifies the noun 'prezentem' in the instrumental case, indicating a characteristic (that the gift was bought).
Najlepszym zakupionym prezentem okazały się te książki.
The best purchased gift turned out to be these books.
This sentence use 'zakupiony' to describe the result of the action (the phone having been bought), making it clear who owns it now.