The Collaborative International Dictionary of English v.0.48:

Exungulate \Ex*un"gu*late\, v. t. [imp. & p. p. Exungulated;
   p. pr. & vb. n. Exungulating.] [L. exungulare to lose the
   hoof, ex out, from + ungula. See Ungula.]
   To pare off, as nails, the hoof, etc. [R.]
   [1913 Webster]