This is the 8928th most frequent Polish word.
sinsayu
The word "sinsayu" does not exist in Polish. It may be a misspelling or misunderstanding.
Here, 'Sinsay' is used as a proper noun, the name of a clothing store.
Wchodzę do sklepu Sinsay, aby kupić nowe ubrania.
I enter the Sinsay store to buy new clothes.
In this context, 'Sinsayu' is the locative form of the proper noun 'Sinsay', used to indicate a location.
Czy chciałbyś iść na zakupy do Sinsayu dzisiaj?
Would you like to go shopping at Sinsay today?
Here, 'Sinsayu' is used in the locative form to indicate promotional offers present at the Sinsay store.