This is the 889th most frequent Polish word.
urzędu
"Urzędu" means "of the office" or "of the authority" (genitive singular of "urząd").
Here, 'urzędu' refers to an official institution or office.
Poszedłem do urzędu, aby załatwić sprawy administracyjne.
I went to the office to handle administrative matters.
Here, 'urzędu' indicates belonging to or associated with the office.
Pracownicy urzędu są bardzo pomocni dla obywateli.
The office staff are very helpful to citizens.
In this sentence, 'urzędu' is used to mean the location of an official administrative place.