Synonyms for Vacant:

adj.

absent (adjective)
gone, empty, lacking, missing, no-show, nonexistent, void, truant, departed, elsewhere, out, away, abstract, absent, Omitted, wanting.
absent-minded; expressionless (adjective)
inane, foolish, empty-headed, vacuous, thoughtless, silly, blank, unintelligent, witless, unthinking.
empty; unoccupied (adjective)
deserted, unfilled, void, unused, uninhabited, available, free, abandoned, clear, bare, devoid.
meaningless (adjective)
meaningless.
new (adjective)
unused.
nonexistent (adjective)
non-subsistent, meaningless, devoid, vacuous, empty, unexisting, barren, nonexistent, void, null.
thoughtless (adjective)
inane, fatuous, thoughtless, brainless, illogical, mindless, blank, unreasonable, unthinking, vacuous, unoccupied, empty-headed, unthoughtful.
unfilled (adjective)
unfilled.
unsubstantial (adjective)
insignificance, apparitional, spectral, unsubstantial, vacuous, chimerical, impalpable, unconcrete, null, ethereal, illusory, empty, unreal, phantasmal, intangible, weightless, nonexistence, inessential, tenuous, immaterial.

n.

open, going, available, usable, seasonal, public, accessible, spare, on offer, unfilled. dark, bleak, inhabited, darkly, free, black, abandoned, uninhabited, beatific, deserted, curious, appealing, occupied, brooding, bug-eyed. appraise, appraisal, biodata, unintelligent, silly, witty, foolish, giddy, applicant, intelligent, bid, apply, application, affirmative action, bidder, application form, witless. bare, full, clear. used, unused. hollow, vain, otiose. vacant (noun)
empty.

Other synonyms:

open, spare, available, public, abandoned, usable, accessible. unused, otiose. vain, free. bare. clear. empty
hollow.
Other relevant words:
unused, going, abandoned, giddy, witless, unfilled, vain, accessible, bare, open, otiose, unintelligent, spare, free, available, clear, bleak, silly, hollow, usable, deserted, foolish, uninhabited.

Usage examples for vacant

  1. The party were all seated, and his the only vacant place. – Put Yourself in His Place by Charles Reade
  2. Back up to the second floor went the children, looking through the vacant rooms. – Bunny Brown and his Sister Sue by Laura Lee Hope
  3. He went to hall rather late on purpose; and instead of sitting in his usual place near Julian, he chose a vacant place at another table. – Julian Home by Dean Frederic W. Farrar