Source : Webster's Revised Unabridged Dictionary (1913)

Aspersorium \As`per*so"ri*um\, n.; pl. {Aspersoria}. [LL. See
   {Asperse}.]
   1. The stoup, basin, or other vessel for holy water in Roman
      Catholic churches.

   2. A brush for sprinkling holy water; an aspergill.