Source : Webster's Revised Unabridged Dictionary (1913)

Conductance \Con*duct"ance\ (k[o^]n*d[u^]k"tans), n. [Conduct,
   v. + -ance.] (Elec.)
   Conducting power; -- the reciprocal of {resistance}. A
   suggested unit is the mho, the reciprocal of the ohm.

         Conductance is an attribute of any specified conductor,
         and refers to its shape, length, and other factors.
         Conductivity is an attribute of any specified material
         without direct reference to its shape or other factors.
                                                  --Sloane's
                                                  Elec. Dict.

Source : WordNet®

conductance
     n : a material's capacity to conduct electricity; measured as
         the reciprocal of electrical resistance