Spectral
Pronunciation : Spec"tral
Part of Speech : a.
Definition : 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. (Opt.)
Defn: Of or pertaining to the spectrum; made by the spectrum; as, spectral colors; spectral analysis. Spectral lemur. (Zo?l.) See Tarsius.
Source : Webster's Unabridged Dictionary, 1913