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refractive index

noun

Definition of refractive index

  1. :  the ratio of the speed of radiation (such as light) in one medium (such as air, glass, or a vacuum) to that in another medium

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First Known Use of refractive index

1839

Medical Dictionary

refractive index

noun

Medical Definition of refractive index

  1. :  index of refraction

Learn More about refractive index

  1. Britannica.com: Encyclopedia article about refractive index

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