What is "coefficient of resistance"

Elasticity \E`las*tic"i*ty\ ([=e]`l[a^]s*t[i^]s"[i^]*t[y^]), n.

1. The quality of being elastic; the inherent property in bodies by which they recover their former figure or dimensions, after the removal of external pressure or altering force; springiness; resilience; tendency to rebound; as, the elasticity of caoutchouc; the elasticity of the air.

2. Power of resistance to, or recovery from, depression or overwork; -- usually referred to as resilience[3].

   Coefficient of elasticity, the quotient of a stress (of a given kind), by the strain (of a given kind) which it produces; -- called also coefficient of resistance.

   Surface of elasticity (Geom.), the pedal surface of an ellipsoid (see Pedal); a surface used in explaining the phenomena of double refraction and their relation to the elastic force of the luminous ether in crystalline media.