The Collaborative International Dictionary of English v.0.48:

Castigate \Cas"ti*gate\, v. t. [imp. & p. p. Castigated; p.
   pr. & vb. n. Castigating.] [L. castigatus, p. p. of
   castigare to correct, punish; castus pure, chaste + agere to
   move, drive. See Caste, and cf. Chasten.]
   1. To punish by stripes; to chastise by blows; to chasten;
      also, to chastise verbally; to reprove; to criticise
      severely.
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   2. To emend; to correct. [Obs.]
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