noun (n)

• submerged marine plant with very long narrow leaves found in abundance along North Atlantic coasts(noun.plant)

  Synonym:
  grass wrack, sea wrack, zostera marina
  

  source: wordnet30
• submerged aquatic plant with ribbonlike leaves; Old World and Australia(noun.plant)

  Synonym:
  tape grass, vallisneria spiralis, wild celery
  

  source: wordnet30
• A plant (Zostera marina), with very long and narrow leaves, growing abundantly in shallow bays along the North Atlantic coast.(noun)

  source: webster1913