Albedo
WordNet
noun
(1) The ratio of reflected to incident light
WiktionaryText
Noun
- The fraction of incident light or radiation reflected by a surface or body, commonly expressed as percentage.
- The whitish inner portion of the rind of citrus fruits that is a source of pectin.
Usage notes
Albedo is to be distinguished from reflectivity, which refers to one specific wavelength (monochromatic radiation).