refracting angle of a prism

from The Collaborative International Dictionary of English v.0.48

Refracting \Re*fract"ing\, a.
   Serving or tending to refract; as, a refracting medium.
   [1913 Webster]

   {Refracting angle of a prism} (Opt.), the angle of a
      triangular prism included between the two sides through
      which the refracted beam passes in the decomposition of
      light.

   {Refracting telescope}. (Opt.) See under {Telescope}.
      [1913 Webster]