This is the 2169th most frequent Turkish word.
koruma
"Koruma" means "protection" or "guard" in English.
Here, "koruma" is a noun meaning "protection" and refers to maintaining the safety or preservation of something.
Onun görevi parkın korunmasını sağlamaktır.
His/her job is to ensure the protection of the park.
In this sentence, "koruma" is a verb root (from "korumak") and refers to the act of protecting.
Bekçi, binayı korumak için görevlendirilmişti.
The guard was assigned to protect the building.
Here, "koruma" is a noun again, highlighting the concept of measures taken for protection or safety.