Reflectivity-and commonly, the word reflectance-refers to the amount of incident radiant energy is mirrored or reversed from a material surface. Some practitioners use the word reflectivity referring to the character of a surface and the word reflectance referring to the energy that is reflected.
Reflectivity does not intimately relate to conduction nor to convection.
In thermodynamics and thermography, reflectivity is represented by lower case Greek letter rho (ρ).
This video (4:23) explores reflectivity and how it is relevant to thermography.