Synonyms for Nonexistent:

adj.

absent (adjective)
no-show, void, lacking, out, abstract, gone, truant, wanting, vacant, missing, Omitted, absent, empty, departed, elsewhere, away.
fictional, not real (adjective)
unreal, gone, empty, null, lost, vacant, absent, missing, departed, void, imaginary, unsubstantial, hypothetical.
imaginary (adjective)
hypothetical.
nonexistent (adjective)
null, non-subsistent, empty, barren, devoid, vacant, void, meaningless, vacuous, unexisting.

n.

lost, misplaced, in absentia, unavailable, unattainable. missing (noun)
hypothetical, imaginary, fictitious, unsubstantial, unreal.
nonexistent (noun)
missing, lacking, nonextant, wanting, absent, vanished.
visionary (noun)
unreal.

Other synonyms:

fancied
imaginary.
Other relevant words:
unsubstantial, lost, nonextant, unavailable, imaginary, unreal, vanished, hypothetical.

Usage examples for nonexistent

  1. He chooses to pretend that I'm nonexistent and I won't stand being ignored! – The Law of Hemlock Mountain by Hugh Lundsford
  2. Meanwhile the Southern States, though unrepresented in Congress, continued their activities, with some interference from Federal authorities, until Congress in 1867 declared their governments nonexistent – The Sequel of Appomattox A Chronicle of the Reunion of the States, Volume 32 In The Chronicles Of America Series by Walter Lynwood Fleming