The Collaborative International Dictionary of English v.0.48:

Phlebotomy \Phle*bot"o*my\, n. [L. phlebotomia, Gr. flebotomi`a;
   fle`ps, flebo`s, a vein + te`mnein to cut: cf. F.
   phl['e]botomie. Cf. Fleam.] (Med.)
   The act or practice of opening a vein for letting blood, in
   the treatment of disease; venesection; bloodletting.
   [1913 Webster]

WordNet (r) 3.0 (2006):

phlebotomy
    n 1: surgical incision into a vein; used to treat
         hemochromatosis [syn: venesection, phlebotomy]