Source : Webster's Revised Unabridged Dictionary (1913)

Perimeter \Per*im"e*ter\, n. [Gr. ?; ? around + ? measure: cf.
   F. p['e]rim[`e]tre.]
   1. (Geom.) The outer boundary of a body or figure, or the sum
      of all the sides.

   2. An instrument for determining the extent and shape of the
      field of vision.

Source : WordNet®

perimeter
     n 1: the boundary line or the area immediately inside the
          boundary [syn: {margin}, {border}]
     2: a line enclosing a plane areas
     3: the size of something as given by the distance around it
        [syn: {circumference}]