Levorotatory

from WordNet (r) 3.0 (2006)

levorotatory
    adj 1: rotating to the left [syn: {levorotary}, {levorotatory},
           {left-handed}]

from The Collaborative International Dictionary of English v.0.48

Levorotatory \Le`vo*ro"ta*to*ry\ (-r[=o]"t[.a]*t[-o]*r[y^]), a.
   [Levo- + rotatory.] (Chem. & Physics)
   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}. [Written
   also {l[ae]vorotatory}.]
   [1913 Webster +PJC]