optical rotatory dispersion 

Initialism: ORD
https://doi.org/10.1351/goldbook.08654
Wavelength dependence of the angle of rotation of the plane of linearly-polarized radiation when transmitted through optically active materials.
Source:
PAC, 2021, 93, 647. (Glossary of methods and terms used in analytical spectroscopy (IUPAC Recommendations 2019)) on page 758 [Terms] [Paper]