D defs.my
Entry 2 senses Webster, 1913

Spectral

/spĕk'-trəl/ · Spec·tral · IPA /ˈspɛktɹəɫ/
01 a. Of or pertaining to a specter; ghosty.
  1. 1.
    Of or pertaining to a specter; ghosty.
    “He that feels timid at the spectral form of evil is not the man to spread light.” — F. W. Robertson.
  2. 2.
    Of or pertaining to the spectrum; made by the spectrum; as, spectral colors; spectral analysis.(Opt.)
Phrases & compounds
Spectral lemur — See Tarsius.