THESAURUS
imponderable
airy, asomatous, astral, atomic, bodiless, corpuscular, decarnate, decarnated, discarnate, disembodied, embryonic, ethereal, evanescent, extramundane, germinal, ghostly, granular, immaterial, impalpable, imperceptible, inappreciable, incomprehensible, inconceivable, incorporate, incorporeal, indiscernible, inestimable, infinitesimal, insensible, insubstantial, intangible, invisible, microcosmic, microscopic, molecular, nonmaterial, nonphysical, nonsubstantial, occult, otherworldly, phantom, psychic, shadowy, spiritual, subatomic, subtle, supernatural, tenuous, thin, transmundane, ultramicroscopic, unapparent, unappreciable, unconcrete, unearthly, unembodied, unextended, unfleshly, unmeasurable, unobservable, unperceivable, unphysical, unseeable, unsolid, unsubstanced, unsubstantial, unweighable, unworldly, weightless
ROGET THESAURUS
imponderable
Levity
N
levity, lightness, imponderability, buoyancy, volatility, feather, dust, mote, down, thistle, down, flue, cobweb, gossamer, straw, cork, bubble, balloon, float, buoy, ether, air, leaven, ferment, barm, yeast, lighter-than-air balloon, helium balloon, hydrogen balloon, hot air balloon, convection, thermal draft, thermal, light, subtile, airy, imponderous,
imponderable, astatic, weightless, ethereal, sublimated, gossamery, suberose, suberous, uncompressed, volatile, buoyant, floating, portable, light as a feather, light as a thistle, light as air, lighter than air, rise like a balloon, float like a balloon.