spectral

Adjective

• resembling or characteristic of a phantom
  • a ghostly face at the window
    
  • a phantasmal presence in the room
    
  • spectral emanations
    
  • spiritual tappings at a seance
    

• of or relating to a spectrum
  • spectral colors
    
  • spectral analysis
    

Related words

• Synonyms: 
  apparitional , ghostlike , ghostly , phantasmal , spiritual