Source : Webster's Revised Unabridged Dictionary (1913)

Vacuity \Va*cu"i*ty\, n. [L. vacuitas. See {Vacuous}.]
   1. The quality or state of being vacuous, or not filled;
      emptiness; vacancy; as, vacuity of mind; vacuity of
      countenance.

            Hunger is such a state of vacuity as to require a
            fresh supply of aliment.              --Arbuthnot.

   2. Space unfilled or unoccupied, or occupied with an
      invisible fluid only; emptiness; void; vacuum.

            A vacuity is interspersed among the particles of
            matter.                               --Bentley.

            God . . . alone can answer all our longings and fill
            every vacuity of our soul.            --Rogers.

   3. Want of reality; inanity; nihility. [R.]

            Their expectations will meet with vacuity.
                                                  --Glanvill.

Source : WordNet®

vacuity
     n 1: the absence of matter [syn: {vacuum}]
     2: total absence of matter [syn: {vacuousness}]
     3: a region empty of matter [syn: {vacuum}]
     4: total lack of meaning or ideas [syn: {inanity}, {senselessness},
         {mindlessness}, {pointlessness}]