The Collaborative International Dictionary of English v.0.48:

biomedicine \bi"o*med`i*cine\ n.
   1. The application of the principles and techniques of the
      natural sciences, especially biology, to investigate and
      solve problems in clinical medicine.
      [PJC]

   2. The investigation of the effects of external environmental
      factors such as weightlessness on the human body.
      [PJC]

WordNet (r) 3.0 (2006):

biomedicine
    n 1: the branch of medical science that applies biological and
         physiological principles to clinical practice
    2: the branch of medical science that studies the ability of
       organisms to withstand environmental stress (as in space
       travel)