noun (n)

• an arm of a sea or ocean partly enclosed by land; larger than a bay(noun.object)

  source: wordnet30
• an unbridgeable disparity (as from a failure of understanding)(noun.attribute)

  Example:
  He felt a gulf between himself and his former friends.
  

  Synonym:
  disconnect, disconnection
  

  source: wordnet30
• a deep wide chasm(noun.object)

  source: wordnet30
• A hollow place in the earth; an abyss; a deep chasm or basin,(noun)

  source: webster1913