Source : Webster's Revised Unabridged Dictionary (1913)

Topiary \Top"i*a*ry\, a. [L. topiarius belonging to ornamental
   gardening, fr. topia (sc. opera) ornamental gardening, fr.
   Gr. ? a place.]
   Of or pertaining to ornamental gardening; produced by
   cutting, trimming, etc.; topiarian.

   {Topiary work}, arbors, shrubbery, hedges, or the like, cut
      and trimmed into fanciful forms, as of animals, buildings,
      etc.

Source : WordNet®

topiary
     n 1: a garden having shrubs clipped or trimmed into decorative
          shapes especially of animals
     2: making decorative shapes by trimming shrubs or trees