dehorn

from WordNet (r) 3.0 (2006)

dehorn
    v 1: prevent the growth of horns of certain animals
    2: take the horns off (an animal)

from The Collaborative International Dictionary of English v.0.48

Dehorn \De*horn"\, v. t. [imp. & p. p. {Dehorned}; p. pr. & vb.
   n. {Dehorning}.]
   To deprive of horns; to prevent the growth of the horns of
   (cattle) by burning their ends soon after they start. See
   {Dishorn}. "Dehorning cattle." --Farm Journal (1886).
   [1913 Webster]