|the ability of substances that are optical isomers to rotate the plane of polarization of a transmitted beam of plane-polarized light|
|a calculus or concretion found in the stomach or intestines of certain animals, esp. ruminants, formerly reputed to be an effective remedy for poison.|
|a gadget; dingus; thingumbob.|
optical activity n.
The property of an asymmetrical molecule in solution to rotate the plane of polarized light either clockwise or counterclockwise.