- spectral - of or relating to a spectrum; "spectral colors"; "spectral analysis"
- apparitional, ghostlike, ghostly, phantasmal, spectral, spiritual - like or being a phantom; "a ghostly face at the window"; "a phantasmal presence in the room"; "spectral emanations"; "spiritual tappings at a seance"
Antonym: natural (indirect, via supernatural)
- apparitional, ghostlike, ghostly, phantasmal, spectral, spiritual - like or being a phantom; "a ghostly face at the window"; "a phantasmal presence in the room"; "spectral emanations"; "spiritual tappings at a seance"