from The American Heritage® Dictionary of the English Language, 5th Edition.
- noun Refractive power.
from The Century Dictionary.
- noun Same as
from Wiktionary, Creative Commons Attribution/Share-Alike License.
- noun physics
refractive power; refraction
Sorry, no etymologies found.
Optically, calcite is uniaxial with negative bi-refringence, the index of refraction for the ordinary ray being greater than for the extraordinary ray; for sodium-light the former is 1.6585 and the latter 1.4862.
The difference, 0.1723, between these two indices gives a measure of the bi-refringence or double refraction.