Levorotatory /(-rō"tȧtō̇ry̆)/

Le·vo·ro·ta·to·ry

Levorotatory

Turning or rotating the plane of polarization of light towards the left; -- applied to crystals and compounds exhibiting optical activity, such as levulose, left-handed quartz crystals, etc. Opposite of dextrorotatory. (Chem. & Physics)