Merriam-Webster Collegiate Dictionary - electricity

 noun  (plural -ties)  Date: 1646  1.  a. a fundamental form of energy observable in positive and negative forms that occurs naturally (as in lightning) or is produced (as in a generator) and that is expressed in terms of the movement and interaction of electrons  b. electric current or power  2. a science that deals with the phenomena and laws of ~  3. keen contagious excitement could feel the ~ in the room