As conductance is the reciprocal of resistance it is measured by the reciprocal ohm or mho.
The exact correlative terms are resistance and conductance, resistivity and conductivity.
This rule may be understood better if we consider the conductance of the conductors in parallel.
conductance con·duc·tance (kən-dŭk'təns)
A measure of a material's ability to conduct electric charge; the reciprocal of the resistance.
The ease with which a fluid or gas enters and flows through a conduit, air passage, or respiratory tract.