WordNet (r) 3.0 (2006):

preview
    n 1: an advertisement consisting of short scenes from a motion
         picture that will appear in the near future [syn:
         preview, prevue, trailer]
    2: a screening for a select audience in advance of release for
       the general public
    v 1: watch (a movie or play) before it is released to the
         general public

Moby Thesaurus II by Grady Ward, 1.0:

111 Moby Thesaurus words for "preview":
   3-D, Cinemascope, Cinerama, Technicolor, Western, animated cartoon,
   anticipation, be a gas, be a hit, bill, black-and-white film, bomb,
   cartoon, chiller, cinema, color film, contemplation, creepie,
   dekko, discretion, documentary, documentary film, dramatize,
   educational film, envisagement, envisionment, eye, eyeful, fail,
   farseeingness, farsightedness, feature, film, flick, flicker, flop,
   forecast, foreglance, foregleam, foreglimpse, forehandedness,
   foreseeing, foresight, foresightedness, headline, horror picture,
   horse opera, leer, leering look, longsightedness, look, look-in,
   looking ahead, lustful leer, make a hit, melodramatize,
   motion picture, motion-picture show, mount, movie, moving picture,
   newsreel, nudie, open, open a show, opening, photodrama, photoplay,
   picture, picture show, pornographic film, prediction, premiere,
   preparation, prepublication, present, prevision, produce, prospect,
   prospection, providence, provision, prudence, put on, readiness,
   regard, sagacity, scenarize, scene, set the stage, short,
   sidelong look, sight, silent, silent film, skin flick, sly look,
   sneak preview, spaghetti Western, stage, star, succeed, talkie,
   talking picture, theatricalize, thriller, trailer, try out,
   underground film, vernissage, view