Source : Webster's Revised Unabridged Dictionary (1913)

Phantasmal \Phan*tas"mal\, a.
   Pertaining to, of the nature of, or resembling, a phantasm;
   spectral; illusive.

Source : WordNet®

phantasmal
     adj : like or being a phantom; "a ghostly face at the window"; "a
           phantasmal presence in the room"; "spectral
           emanations"; "spiritual tappings at a seance" [syn: {apparitional},
            {ghostlike}, {ghostly}, {spectral}, {spiritual}]