Source : Webster's Revised Unabridged Dictionary (1913)

Physics \Phys"ics\, n. [See {Physic}.]
   The science of nature, or of natural objects; that branch of
   science which treats of the laws and properties of matter,
   and the forces acting upon it; especially, that department of
   natural science which treats of the causes (as gravitation,
   heat, light, magnetism, electricity, etc.) that modify the
   general properties of bodies; natural philosophy.

   Note: Chemistry, though a branch of general physics, is
         commonly treated as a science by itself, and the
         application of physical principles which it involves
         constitute a branch called chemical physics, which
         treats more especially of those physical properties of
         matter which are used by chemists in defining and
         distinguishing substances.

Source : WordNet®

physics
     n : the science of matter and energy and their interactions
         [syn: {physical science}, {natural philosophy}]