This is the 4248th most frequent Turkish word.
polisin
"Polisin" means "your police" or "the police's" in English, depending on context.
In this sentence, the word "polisin" is used in its possessive form with a genitive meaning, indicating the action or origin related to the police.
Polisin geldiği yer burası.
This is the place where the police came.
Here, "polisin" indicates the subject in a genitive-possessive construction which highlights the action being attributed to the police.
Arabanın anahtarını polisin verdiğini söylediler.
They said that the police gave the car key.
The usage of "polisin" here refers to the possessive role of the police in conducting the interrogation.