of or pertaining to a specter; ghostly; phantom.

resembling or suggesting a specter.

of, pertaining to, or produced by a spectrum or spectra.

resembling or suggesting a spectrum or spectra.

adjective

apparitional , eerie , haunted , illusory , phantasmal , phantom , scary , shadowy , spiritual , spooky , supernatural , cadaverous , deadly , deathlike , deathly , ghostlike , ghostly , creepy , phantomlike , unearthly