microvolt

from WordNet (r) 3.0 (2006)

microvolt
    n 1: a unit of potential equal to one millionth of a volt

from The Collaborative International Dictionary of English v.0.48

Microvolt \Mi`cro*volt"\ (m[imac]"kr[-o]*v[=o]lt`), n. [Micro- +
   volt.] (Elec.)
   A measure of electro-motive force; the millionth part of one
   volt.
   [1913 Webster]