Roget's Thesaurus

#4. Unsubstantiality

Nouns

unsubstantiality, insubstantiality; nothingness, nihility; no degree, no part, no quantity, no thing. nothing, naught, nil, nullity, zero, cipher, no one, nobody; never a one, ne'er a one [Contr.]; no such thing, none in the world; nothing whatever, nothing at all, nothing on earth; not a particle etc. (smallness) 32; all talk, moonshine, stuff and nonsense; matter of no importance, matter of no consequence. thing of naught, man of straw, John Doe and Richard Roe, faggot voter; nominis umbra [Lat.], nonentity; flash in the pan, vox et praeterea nihil [Lat.]. shadow; phantom etc. (fallacy of vision) 443; dream etc. (imagination) 515; ignis fatuus [Lat.] etc. (luminary) 423; such stuff as dreams are made of [Tempest]; air, thin air, vapor; bubble etc. 353; baseless fabric of a vision [Tempest]; mockery. hollowness, blank; void etc. (absence) 187. inanity, fool's paradise.

Verbs

vanish, evaporate, fade, dissolve, melt away; disappear etc. 449.

Adjectives

unsubstantial; baseless, groundless; ungrounded; without foundation, having no foundation. visionary etc. (imaginary) 515; immaterial etc. 137; spectral etc. 980; dreamy; shadowy; ethereal, airy; cloud built, cloud formed; gossamery, illusory, insubstantial, unreal. vacant, vacuous; empty etc. 187; eviscerated; blank, hollow; nominal; null; inane.

Phrases

there's nothing in it; an ocean of dreams without a sound [Shelley].