reflectance

noun

re·​flec·​tance ri-ˈflek-tən(t)s 

: the fraction of the total radiant flux incident upon a surface that is reflected and that varies according to the wavelength distribution of the incident radiation

The basis of this approach is that different materials exhibit unique reflectance and emission properties as a function of wavelength across the electromagnetic spectrum.

—Jeffrey Star and John Estes

broadly, nontechnically : reflectivity

screen reflectance

compare albedo

Examples of reflectance in a Sentence

Recent Examples on the Web

Ice signaled its presence via the scattering and reflectance of light, as seen by ShadowCam. —K. R. Callaway, Scientific American, 18 Mar. 2026

According to the team, the greatest power losses happen because the dust enhances the presence and reflectance of cirrus clouds, reducing how much radiation that reaches solar panels. —Laura Baisas, Popular Science, 12 Mar. 2026

The upper surface is reported to have low reflectance for comfortable viewing in bright daylight, or night owls can take advantage of the adjustable front light. —New Atlas, 11 Nov. 2025

In one study, researchers used UV reflectance analysis to observe whether applying moisturizing cream before or after sunscreen impacted the sunscreen's effectiveness. —Anna Giorgi, Verywell Health, 30 Sep. 2025

Word History

First Known Use

1893, in the meaning defined above

Medical Definition

reflectance

noun

re·​flec·​tance ri-ˈflek-tən(t)s 

: the fraction of the total radiant flux incident upon a surface that is reflected and that varies according to the wavelength distribution of the incident radiation

called also reflection coefficient, reflection factor