sunken
adj.adj. lower than the surface around it, or having fallen deep into something. You use this to describe things like eyes that look tired or ships that have gone to the bottom of the sea.
adj. situated at a lower level than the surrounding area; having fallen or settled deep into a surface. Often used to describe facial features affected by age or illness, or objects submerged in water.
The divers found a sunken ship at the bottom of the lake.
After working three night shifts in a row, he had dark circles and sunken eyes.
The garden featured a sunken patio that provided a private, sheltered space for outdoor dining away from the wind.
Typically used as an attributive adjective before a noun. While it originated as a past participle of 'sink', it now functions primarily as a descriptive adjective.