The Collaborative International Dictionary
laevorotation
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.
Wiktionary
laevorotation
n. (alternative form of levorotation English)