The Collaborative International Dictionary of English v.0.48:

electric current \electric current\, electrical current
\electrical current\,
   the movement of electrically charged particles, atoms, or
   ions, through solids, liquids, gases, or free space; the term
   is usually used of relatively smooth movements of electric
   charge through conductors, whether constant or variable.
   Sudden movements of charge are usually referred to by other
   terms, such as spark or lightning or discharge. In
   metallic conductors the electric current is usually due to
   movement of electrons through the metal. The current is
   measured as the rate of movement of charge per unit time, and
   is counted in units of amperes. As a formal definition, the
   direction of movement of electric current is considered as
   the same as the direction of movement of positive charge, or
   in a direction opposite to the movement of negative charge.
   Electric current may move constantly in a single direction,
   called direct current (abbreviated DC), or may move
   alternately in one direction and then the opposite direction,
   called alternating current (abbreviated AC).
   [PJC]