Source : Webster's Revised Unabridged Dictionary (1913)

Ablation \Ab*la"tion\, n. [L. ablatio, fr. ablatus p. p. of
   auferre to carry away; ab + latus, p. p. of ferre carry: cf.
   F. ablation. See {Tolerate}.]
   1. A carrying or taking away; removal. --Jer. Taylor.

   2. (Med.) Extirpation. --Dunglison.

   3. (Geol.) Wearing away; superficial waste. --Tyndall.

Source : WordNet®

ablation
     n 1: surgical removal of a body part or tissue [syn: {extirpation},
           {cutting out}, {excision}]
     2: the erosive process that reduces the size of glaciers