The Collaborative International Dictionary of English v.0.48:

Castration \Cas*tra"tion\, n. [L. castratio; cf. F. castration.]
   The act of castrating.
   [1913 Webster]

WordNet (r) 3.0 (2006):

castration
    n 1: neutering a male animal by removing the testicles [syn:
         castration, emasculation]
    2: surgical removal of the testes or ovaries (usually to inhibit
       hormone secretion in cases of breast cancer in women or
       prostate cancer in men); "bilateral castration results in
       sterilization"
    3: the deletion of objectionable parts from a literary work
       [syn: expurgation, castration]