Source : Webster's Revised Unabridged Dictionary (1913)

Biochemistry \Bi`o*chem"is*try\, n. [Gr. ? life + E. chemistry.]
   (Biol.)
   The chemistry of living organisms; the chemistry of the
   processes incidental to, and characteristic of, life.

Source : WordNet®

biochemistry
     n : the organic chemistry of compounds and processes occuring in
         organisms; the effort to understand biology within the
         context of chemistry