What is another word for "solidity"?

Roget's Thesaurus (1911) lists these synonyms for "solidity": absence, cavernous, compressibility, compressible, diffusion, dilatation, dilate, ether, evaporation, expand, expansion, fine, flimsy, gas, hollow, inflation, light, rare, rarefaction, rarefiable, rarefy, rarity, slight, sponginess, spongy, subtile, subtility, subtilization, subtilize, subtilty, subtlety, tenuity, tenuous, thin, unsubstantial, vaporization.