chemotherapy

from WordNet (r) 3.0 (2006)

chemotherapy
    n 1: the use of chemical agents to treat or control disease (or
         mental illness)

from The Collaborative International Dictionary of English v.0.48

chemotherapy \chemotherapy\ n.
   the use of chemical agents to treat or control disease (or
   mental illness); -- also used especially in reference to the
   use of chemicals to treat cancer.
   [WordNet 1.5 +PJC]