[1] : The Collaborative International Dictionary of English v.0.48

ethereal \ethe"real\, a.
   1. pertaining to the hypothetical upper, purer air, or to the
      higher regions beyond the earth or beyond the atmosphere;
      celestial; as, ethereal space; ethereal regions.
      1913 webster

            go, heavenly guest, ethereal messenger. --milton.
      1913 webster

   2. consisting of ether; hence, exceedingly light or airy;
      tenuous; spiritlike; characterized by extreme delicacy, as
      form, manner, thought, etc.
      1913 webster

            vast chain of being, which from god began,
            natures ethereal, human, angel, man.  --pope.
      1913 webster

   3. chem. pertaining to, derived from, or resembling, ether;
      as, ethereal salts.
      1913 webster

   ethereal oil. chem. see essential oil, under
      essential.

   ethereal oil of wine chem., a heavy, yellow, oily liquid
      consisting essentially of etherin, etherol, and ethyl
      sulphate. it is the oily residuum left after
      etherification. called also heavy oil of wine
      distinguished from oil of wine, or oenanthic ether.

   ethereal salt chem., a salt of some organic radical as a
      base; an ester.
      1913 webster
see also:
ethereal oil essential oil essential ethereal oil of wine heavy oil of wine ethereal salt 

[2] : WordNet (r) 2.0

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
see also:
aeriform aerial airy aery celestial supernal 
gossamer 

[3] : Moby Thesaurus II by Grady Ward, 1.0

229 moby thesaurus words for "ethereal":
   elysian, olympian, adulterated, aerial, aeriform, aerodynamic,
   aerostatic, aery, air-built, airish, airlike, airy, alfresco,
   altitudinous, ascending, asomatous, aspiring, astral, atmospheric,
   attenuate, attenuated, beatific, beatified, blessed, bodiless,
   boyish, breezy, bubbly, celestial, chimeric, chimerical,
   cloud-born, cloud-built, cloud-woven, colossal, cut, decarnate,
   decarnated, delicate, diaphanous, dilute, diluted, discarnate,
   disembodied, dominating, downy, dreamlike, ectoplasmic, elevated,
   eminent, empyreal, empyrean, etheric, exalted, exposed,
   extramundane, extraterrestrial, fanciful, fatuitous, fatuous,
   feathery, filmy, fine, fine-drawn, finespun, flimsy, fluffy, foamy,
   fragile, frail, from on high, frothy, fuming, fumy, gaseous,
   gasified, gasiform, gaslike, gassy, gauzy, ghostish, ghostlike,
   ghostly, ghosty, girlish, glorified, gossamer, gossamery, gracile,
   haughty, heavenly, high, high-pitched, high-reaching, high-set,
   high-up, illusory, imaginary, immaterial, impalpable, imponderable,
   imponderous, in glory, incorporate, incorporeal, insubstantial,
   intangible, lacy, leger, light, light as air, lighter than vanity,
   lofty, mephitic, miasmal, miasmatic, miasmic, misty, monumental,
   mounting, mousse, nonmaterial, nonphysical, occult, open-air,
   otherworldly, outtopping, overlooking, overtopping, oxyacetylene,
   oxygenous, ozonic, papery, paradisaic, paradisal, paradisiac,
   paradisic, phantasmal, phantasmic, phantom, phantomic, phantomlike,
   pneumatic, prominent, psychic, rare, rarefied, reeking, reeky,
   roomy, shadowy, slender, slenderish, slight, slight-made, slim,
   slimmish, slinky, small, smoking, smoky, soaring, souffle,
   specterlike, spectral, spiring, spiritual, spirituous, steaming,
   steamy, steep, sublime, subtile, subtle, superlative, supernal,
   supernatural, svelte, sylphlike, tenuous, thin, thin-bodied,
   thin-set, thin-spun, thinned, thinned-out, thinnish, threadlike,
   topless, toplofty, topping, towering, towery, transcendental,
   transmundane, tropospheric, uncompact, uncompressed, unearthly,
   unembodied, unextended, unfleshly, unheavy, unphysical, unreal,
   unsubstantial, unworldly, uplifted, upreared, vague, vaporing,
   vaporish, vaporlike, vaporous, vapory, volatile, wasp-waisted,
   watered, watered-down, watery, weak, weightless, willowy, windy,
   wiredrawn, wispy, wraithlike, wraithy, yeasty

Ethereal >> E Words
Ethereal, definition of term: Ethereal
ethereal_pag1.html

Ethereal Salt >> E Words
Ethereal Salt, definition of term: Ethereal Salt
ethereal+salt_pag1.html