Source : Webster's Revised Unabridged Dictionary (1913)

Lustrate \Lus"trate\, v. t. [imp. & p. p. {Lustrated}; p. pr. &
   vb. n. {Lustrating}.] [L. lustratus, p. p. of lustrare to
   lustrate, fr. lustrum. See {Lustrum}.]
   To make clear or pure by means of a propitiatory offering; to
   purify.

         We must purge, and cleanse, and lustrate the whole
         city.                                    --Hammond.

Source : WordNet®

lustrate
     v : purify by means of a ritual; also used in post-Communist
         countries to refer to the political cleansing of former
         officials