The Collaborative International Dictionary of English v.0.48:

Excision \Ex*ci"sion\, n. [L. excisio: cf. F. excision. See
   Excide.]
   1. The act of excising or cutting out or off; extirpation;
      destruction.
      [1913 Webster]

            Such conquerors are the instruments of vengeance on
            those nations that have . . . grown ripe for
            excision.                             --Atterbury.
      [1913 Webster]

   2. (Eccl.) The act of cutting off from the church;
      excommunication.
      [1913 Webster]

   3. (Surg.) The removal, especially of small parts, with a
      cutting instrument. --Dunglison.
      [1913 Webster]

WordNet (r) 3.0 (2006):

excision
    n 1: the omission that is made when an editorial change shortens
         a written passage; "an editor's deletions frequently upset
         young authors"; "both parties agreed on the excision of the
         proposed clause" [syn: deletion, excision, cut]
    2: surgical removal of a body part or tissue [syn: ablation,
       extirpation, cutting out, excision]
    3: the act of banishing a member of a church from the communion
       of believers and the privileges of the church; cutting a
       person off from a religious society [syn: excommunication,
       excision]
    4: the act of pulling up or out; uprooting; cutting off from
       existence [syn: extirpation, excision, deracination]