What is the meaning of shadow?

noun

• Shade within clear boundaries.
• An unilluminated area.
  • usage: "he moved off into the darkness"
  • synonyms: darkness, dark
• Something existing in perception only.
  • usage: "a ghostly apparition at midnight"
  • synonyms: apparition, phantom, phantasm, phantasma, fantasm
• A premonition of something adverse.
  • usage: "a shadow over his happiness"
• An indication that something has been present.
  • usage: "there wasn't a trace of evidence for the claim"; "a tincture of condescension"
  • synonyms: trace, vestige, tincture
• Refuge from danger or observation.
  • usage: "he felt secure in his father's shadow"
• A dominating and pervasive presence.
  • usage: "he received little recognition working in the shadow of his father"
• A spy employed to follow someone and report their movements.
  • synonyms: tail, shadower
• An inseparable companion.
  • usage: "the poor child was his mother's shadow"

verb

• Follow, usually without the person's knowledge.
  • usage: "The police are shadowing her"
• Cast a shadow over.
  • synonyms: shade, shade off
• Make appear small by comparison.
  • usage: "This year's debt dwarfs that of last year"
  • synonyms: overshadow, dwarf