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English definition of “refraction”

refraction

noun [U]  /rɪˈfræk·ʃən/ us  
absolute index of refraction The absolute index of refraction is a calculation of the relationship between the speed of light moving through a medium (= substance) and the speed of light in a vacuum (= place with no matter in it) angle of refraction The angle of refraction is the angle that a beam of light or other energy that is refracted by a surface makes with a line vertical to that surface.
(Definition of refraction from the Cambridge Academic Content Dictionary © Cambridge University Press)
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