noun, noun or participle which takes 'suru', intransitive verb
cave-in; collapse; sinking; depression; subsidence
Refers to a surface sinking or collapsing inward, such as ground subsidence, a roof cave-in, or a depressed fracture. Used both as a noun and as a suru-verb.
道路が陥没して大きな穴ができた。
The road caved in, creating a large hole.
The ground subsided due to the earthquake.
頭蓋骨陥没骨折と診断された。
He was diagnosed with a depressed skull fracture.