Source : Webster's Revised Unabridged Dictionary (1913)

Ablution \Ab*lu`tion\, n. [L. ablutio, fr. abluere: cf. F.
   ablution. See {Abluent}.]
   1. The act of washing or cleansing; specifically, the washing
      of the body, or some part of it, as a religious rite.

   2. The water used in cleansing. ``Cast the ablutions in the
      main.'' --Pope.

   3. (R. C. Ch.) A small quantity of wine and water, which is
      used to wash the priest's thumb and index finger after the
      communion, and which then, as perhaps containing portions
      of the consecrated elements, is drunk by the priest.

Source : WordNet®

ablution
     n : the ritual washing of a priest's hands or of sacred vessels