WordNet (r) 3.0 (2006):

viewpoint
    n 1: a mental position from which things are viewed; "we should
         consider this problem from the viewpoint of the Russians";
         "teaching history gave him a special point of view toward
         current events" [syn: point of view, viewpoint,
         stand, standpoint]
    2: a place from which something can be viewed; "from that
       vantage point he could survey the whole valley" [syn:
       vantage point, viewpoint]

Moby Thesaurus II by Grady Ward, 1.0:

76 Moby Thesaurus words for "viewpoint":
   Anschauung, angle, angle of vision, aspect, attitude, base, basis,
   coign of vantage, configuration, context, direction, distance,
   effect, eidolon, estimation, eye, facet, fashion, feature, figure,
   footing, form, frame of reference, framework, gestalt, ground,
   guise, image, imago, impression, light, likeness, lineaments, long,
   look, manner, mental outlook, outlook, perspective, phase, phasis,
   place, point of view, position, post, posture, reference,
   reference system, regard, respect, seat, seeming, semblance, shape,
   side, sight, simulacrum, situation, slant, stance, stand, standing,
   standpoint, station, status, style, system, total effect, twist,
   universe, vantage, vantage point, venue, view, way of thinking,
   wise