Possible Definitions:
1. Deflection (n.) 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. Deflection (n.) The deviation of a shot or ball from its true course.
3. Deflection (n.) A deviation of the rays of light toward the surface of an opaque body; inflection; diffraction.
4. Deflection (n.) The bending which a beam or girder undergoes from its own weight or by reason of a load.