The Collaborative International Dictionary of English v.0.48:

Motion picture \Mo"tion pic"ture\
   1. A series of pictures on a strip of film, taken at regular
      intervals in rapid succession (now usually 24 frames per
      second for ordinary work) by a special camera, intended to
      capture the image of objects in motion.
      [PJC]

   2. the display of the images captured on a motion
      picture[1], presented to the eye in very rapid succession
      by projection from a special apparatus (a movie
      projector), with shows some or all of the objects in the
      picture represented in changing positions, producing, by
      persistence of vision, the optical effect of a continuous
      picture in which the objects appear to move as they did in
      the original scene.

   Syn: movie, moving picture, flick. [Webster 1913 Suppl. +PJC]

   3. The conceptual or informational content of a motion
      picture[1]; the actions or events represented in a
      motion picture[1]; the story line of a movie. "One of
      the great punch lines in motion picture history is `Round
      up the usual suspects.' from `Casablanca'." [PJC]

WordNet (r) 3.0 (2006):

motion picture
    n 1: a form of entertainment that enacts a story by sound and a
         sequence of images giving the illusion of continuous
         movement; "they went to a movie every Saturday night"; "the
         film was shot on location" [syn: movie, film,
         picture, moving picture, moving-picture show, motion
         picture, motion-picture show, picture show, pic,
         flick]