This is the 10344th most frequent Japanese word.
骨折
Bone fracture.
In this sentence, '骨折 (kossetsu)' is used as a verb to indicate the action of breaking a bone due to an accident.
彼はスキーで転んで骨折しました。
He fell while skiing and broke a bone.
'骨折 (kossetsu)' is used as a noun here, referring to the condition of having a fracture.
骨折が治るには時間がかかります。
Recovering from a fracture takes time.
The word '骨折 (kossetsu)' again appears as a noun, used to indicate fractures that can occur and measures to prevent them.