refractive

• POS: Adjective
• HYPHEN: re=frac=tive

CIDE DICTIONARY

refractive, a. [Cf. F. réfractif. See Refract.].

 Serving or having power to refract, or turn from a direct course; pertaining to refraction; as, refractive surfaces; refractive powers.  [1913 Webster]

Refractive index. (Opt.) See Index of refraction, under Index. -- Absolute refractive index (Opt.), the index of refraction of a substances when the ray passes into it from a vacuum. -- Relative refractive index (of two media) (Opt.), the ratio of the sine of the angle of incidence to the sine of the angle of refraction for a ray passing out of one of the media into the other.

OXFORD DICTIONARY

refractive, adj. of or involving refraction.

Idiom

refractive index the ratio of the velocity of light in a vacuum to its velocity in a specified medium.