Deflection

n.
  1. The act of turning aside, or state of being turned aside; a turning from a right line or proper course; a bending, esp. downward; deviation.
  2. (Gunnery) The deviation of a shot or ball from its true course.
  3. (Opt.) A deviation of the rays of light toward the surface of an opaque body; inflection; diffraction.
  4. (Engin.) The bending which a beam or girder undergoes from its own weight or by reason of a load.