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.
Definition Of Axis. An Axis is a line about which a figure is drawn, measured, rotated, etc. The horizontal line and the vertical line on a coordinate plane are known as the X-axis and the Y-axis respectively. The plural of axis is axes. In a three-dimensional coordinate plane X, Y, and Z are the three axes.