noun (n)

• a region marking a boundary(noun.shape)

  Synonym:
  threshold, verge
  

  source: wordnet30
• the edge of a steep place(noun.location)

  source: wordnet30
• the limit beyond which something happens or changes(noun.attribute)

  Example:
  On the brink of bankruptcy.
  

  Synonym:
  verge
  

  source: wordnet30
• The edge, margin, or border of a steep place, as of a precipice; a bank or edge, as of a river or pit; a verge; a border; as, the brink of a chasm. Also Fig.(noun)

  source: webster1913