Reflectance values express the percentage of light that is reflected back from a surface, the difference having been absorbed or transmitted by the surface.
Definition of AXIAL. 1. : of, relating to, or having the characteristics of an axis.
Radial is a geometric term of location which can refer to: 1  Vector (geometric), a line. 2  Radius, adjective form of. 3  A radial pattern is one that appears to radiate from a point, like the spokes from the hub of a wheel.  A directional coordinate in a polar coordinate 1  system. A bearing from a waypoint, such as a  VOR.