D defs.my
Entry 2 senses Webster, 1913

Refract

/(rē̇*frăkt")/ · Re·fract · IPA
01 v. t. To bend sharply and abruptly back; to break off.
imp. & p. p. Refracted; p. pr. & vb. n. Refracting
  1. 1.
    To bend sharply and abruptly back; to break off.
  2. 2.
    To break the natural course of, as rays of light or heat, when passing from one transparent medium to another of different density; to cause to deviate from a direct course by an action distinct from reflection; as, a dense medium refracts the rays of light as they pass into it from a rare medium.