Synonyms of the word 
REFLECTANCE → COEFFICIENT - REFLECTIVITY
reflectance
- n. (physics) The ratio of the flux reflected to that incident on a surface.
coefficient
- adj. cooperating.
- n. (mathematics) A constant by which an algebraic term is multiplied.
- n. A number, value or item that serves as a measure of some property or characteristic.
reflectivity
- n. The quality of being reflective.
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