ethereal
     adj 1: characterized by lightness and insubstantiality; as
            impalpable or intangible as air; "figures light and
            aeriform come unlooked for and melt away"- Thomas
            Carlyle; "aerial fancies"; "an airy apparition";
            "physical rather than ethereal forms" [syn: {aeriform},
             {aerial}, {airy}, {aery}]
     2: of or containing or dissolved in ether; "ethereal solution"
     3: of heaven or the spirit; "celestial peace"; "ethereal
        melodies"; "the supernal happiness of a quiet death" [syn:
         {celestial}, {supernal}]
     4: characterized by unusual lightness and delicacy; "this
        smallest and most ethereal of birds"; "gossamer shading
        through his playing" [syn: {gossamer}]
Source: WordNet® 2.0