THESAURUS
weightless
airy, bodiless, bubbly, downy, ethereal, featherweight, feathery, fluffy, foamy, frothy, gossamery, immaterial, impalpable, imponderable, imponderous, incorporeal, insubstantial, intangible, leger, light, light as air, lighter than vanity, lightweight, mousse, nonsubstantial, souffle, unconcrete, unheavy, unsolid, unsubstanced, unsubstantial, volatile, yeasty
ROGET THESAURUS
weightless
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.