[1] : The Collaborative International Dictionary of English v.0.48

alter \al"ter\, v. t. imp.  p. p. altered; p. pr.  vb. n.
   altering. f. alt'erer, ll. alterare, fr. l. alter
   other, alius other. cf. else, other.
   1. to make otherwise; to change in some respect, either
      partially or wholly; to vary; to modify. "to alter the
      king's course." "to alter the condition of a man." "no
      power in venice can alter a decree." --shak.
      1913 webster

            it gilds all objects, but it alters none. --pope.
      1913 webster

            my covenant will i not break, nor alter the thing
            that is gone out of my lips.          --ps. lxxxix.
                                                  34.
      1913 webster

   2. to agitate; to affect mentally. obs. --milton.
      1913 webster

   3. to geld. colloq.
      1913 webster

   syn: change, alter.

   usage: change is generic and the stronger term. it may
          express a loss of identity, or the substitution of one
          thing in place of another; alter commonly expresses a
          partial change, or a change in form or details without
          destroying identity.
          1913 webster
see also:
altered altering else other change alter 

[2] : WordNet (r) 2.0

altering
     n : the sterilization of an animal; "they took him to the vet
         for neutering" syn: neutering, fixing
see also:
neutering fixing 

Altering >> A Words
Altering, definition of term: Altering
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