Levorotation \Le`vo*ro*ta"tion\, n. [Written also
{l[ae]vorotation}.] [Levo- + rotation.] (Physics & Chem.)
Rotation in the direction of an outgoing right-handed screw;
counter-clockwise rotation; -- applied chiefly to the turning
of the plane of polarization of light.
[Webster 1913 Suppl.]