Source : Webster's Revised Unabridged Dictionary (1913)

Expurgate \Ex"pur*gate\ (?; 277), v. t. [imp. & p. p.
   {Expurgated}; p. pr. & vb. n. {Expurgating}.] [L. expurgatus,
   p. p. of expurgare to purge, purify; ex out, from + purgare
   to cleanse, purify, purge. See {Purge}, and cf. {Spurge}.]
   To purify; to clear from anything noxious, offensive, or
   erroneous; to cleanse; to purge; as, to expurgate a book.

Source : WordNet®

expurgate
     v : edit by omitting or modifying parts considered indelicate;
         "bowdlerize a novel" [syn: {bowdlerize}, {bowdlerise}, {castrate},
          {shorten}]