Mawson, C.O.S., ed. (1870–1938). Roget’s International Thesaurus. 1922.

Class I. Words Expressing Abstract Relations
Section I. Existence
1. Being, in the Abstract

2. Nonexistence.

   NOUN:NONEXISTENCE, nonsubsistence; inexistence; nonentity, nil [L.]; negativeness &c. adj.; nullity; nihility, nihilism; tabula rasa [L.], blank; abeyance; absence [See Absence]; no such thing [See Unsubstantiality]; nonbeing, nothingness, oblivion, non esse [L.].
  ANNIHILATION; extinction (destruction) [See Destruction]; extinguishment, extirpation, Nirvana, obliteration.
   VERB:NOT EXIST [See Existence]; have no existence [See Existence]; be null and void; cease to exist [See Existence]; pass away, perish; be or become extinct &c. adj.; die out; disappear [See Disappearance]; melt away, dissolve, leave not a rack behind; go, be no more; die [See Death].
  ANNIHILATE, render null, nullify; abrogate [See Abrogation]; destroy [See Destruction]; take away; remove (displace) [See Displacement]; obliterate, extirpate, deracinate [rare].
   ADJECTIVE:INEXISTENT, nonexistent [See Existence]; negative, blank; null, minus, missing, omitted; absent [See Absence]; insubstantial, shadowy, spectral, visionary.
  UNREAL, potential, virtual; baseless, in nubibus [L.]; unsubstantial [See Unsubstantiality]; vain.
  UNBORN, uncreated, unbegotten, unconceived, unproduced, unmade.
  PERISHED, annihilated &c. v.; extinct, exhausted, gone, lost, departed; defunct (dead) [See Death].
  FABULOUS, ideal (imaginary) [See Imagination]; supposititious [See Supposition].
   ADVERB:negatively, virtually &c. adj.
  1. Non ens.
  2. And what’s her history? A blank, my Lord.—Twelfth Night