noun
police, police department
A1
Polizei (die Polizei) means the police as a force or, secondarily, a police station/department. It's feminine and usually used as a singular collective (die Polizei). A plural Polizeien exists for separate forces but is uncommon. Declension: nominative die Polizei, dative der Polizei.
Examples
Er arbeitet in der örtlichen Polizei.
He works at the local police department.
Der Zeuge rief die Polizei, weil ein Wagen gegen einen Baum fuhr und Menschen verletzt wurden.
The witness called the police because a car drove into a tree and people were injured.
Die Polizei hat den Unfall aufgenommen.
The police took a report of the accident.
Details
Mnemonics
Imagine a police car with 'Polizei' written on the side.
Polizei sounds a bit like 'police' — same meaning.
die (feminine): imagine a female officer representing 'die Polizei'.
Notes
Usually used as a collective noun without plural in everyday speech; 'Polizeien' exists for multiple police forces.