Source : Webster's Revised Unabridged Dictionary (1913)

Motor car \Motor car\, or Motorcar \Mo"tor*car`\, n.
   1. An automobile, locomobile, or locomotive designed to run
      and be steered on a street or roadway; esp., an automobile
      specially designed for passengers.

   2. (Elec. Railroads) Any car containing motors for
      propulsion. [U. S.]

Source : WordNet®

motorcar
     n : 4-wheeled motor vehicle; usually propelled by an internal
         combustion engine; "he needs a car to get to work" [syn:
         {car}, {auto}, {automobile}, {machine}]