noun (n)

• the boundary line or the area immediately inside the boundary(noun.shape)

  Synonym:
  border, margin
  

  source: wordnet30
• a line enclosing a plane areas(noun.shape)

  source: wordnet30
• the size of something as given by the distance around it(noun.attribute)

  Synonym:
  circumference
  

  source: wordnet30
• The outer boundary of a body or figure, or the sum of all the sides.(noun)

  source: webster1913