What is the meaning of sunken?

verb

• Fall or descend to a lower place or level.
  • usage: "He sank to his knees"
  • synonyms: sink, drop, drop down
• Cause to sink.
  • usage: "The Japanese sank American ships in Pearl Harbor"
  • synonyms: sink
• Pass into a specified state or condition.
  • usage: "He sank into nirvana"
  • synonyms: sink, pass, lapse
• (v.) ()
  • synonyms: sink, settle, go down, go under
• Descend into or as if into some soft substance or place.
  • usage: "He sank into bed"; "She subsided into the chair"
  • synonyms: sink, subside
• Appear to move downward.
  • usage: "The sun dipped below the horizon"; "The setting sun sank below the tree line"
  • synonyms: dip, sink
• Fall heavily or suddenly; decline markedly.
  • usage: "The real estate market fell off"
  • synonyms: slump, fall off, sink
• Fall or sink heavily.
  • usage: "He slumped onto the couch"; "My spirits sank"
  • synonyms: slump, slide down, sink
• Embed deeply.
  • usage: "She sank her fingers into the soft sand"; "He buried his head in her lap"
  • synonyms: bury, sink

adjective

• Having a sunken area.
  • usage: "hunger gave their faces a sunken look"
  • synonyms: deep-set, recessed