The Collaborative International Dictionary of English v.0.48:

Gossamery \Gos"sa*mer*y\, a.
   Like gossamer; flimsy.
   [1913 Webster]

         The greatest master of gossamery affectation. --De
                                                  Quincey.
   [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

128 Moby Thesaurus words for "gossamery":
   air-built, airy, attenuate, attenuated, breakable, brittle, bubbly,
   capillary, cheap-jack, chimerical, cirrose, cirrous, clear,
   clear as crystal, cloud-built, cobwebby, crumbly, crystal,
   crystal-clear, crystalline, dainty, delicate, delicately weak,
   diaphane, diaphanous, downy, dreamlike, effeminate, ethereal,
   fanciful, fatuitous, fatuous, feathery, fibered, fibroid, fibrous,
   filmy, fine, fine-drawn, fine-grained, finespun, flagelliform,
   flimsy, flossy, fluffy, foamy, fragile, frail, frangible, frothy,
   funicular, fuzzy, gaseous, gauzy, gimcrack, gimcracky, gossamer,
   hairlike, hairy, illusory, imaginary, imponderous, jerry,
   jerry-built, leger, ligamental, light, light as air,
   light-pervious, lighter than vanity, lightweight, limpid, lucid,
   mousse, namby-pamby, nonopaque, papery, pasteboardy, peekaboo,
   pellucid, phantomlike, pubescent, puny, rarefied, refined,
   revealing, ropy, satin, satiny, see-through, shadowy, shattery,
   sheer, silky, sissified, sleazy, slight, smooth, souffle,
   spirituous, stringy, subtile, subtle, tacky, taeniate, taeniform,
   tenuous, thin, thin-spun, threadlike, thready, transparent,
   transpicuous, unclouded, unheavy, unreal, unsubstantial, vaporous,
   velutinous, velvety, volatile, weightless, windy, wiredrawn, wiry,
   wispy, womanish, yeasty