https://doi.org/10.1351/goldbook.08292
Reflection of electromagnetic radiation from a surface such that each incident ray is reflected at the same angle to the surface normal as the incident ray, but on the opposing side of the surface normal in the plane formed by incident and reflected rays.
Note:
An image reflected by the surface in this way is reproduced in mirror-like (specular) fashion.
An image reflected by the surface in this way is reproduced in mirror-like (specular) fashion.