landmark

• n.
  • the position of a prominent or well-known object in a particular landscape

    "the church steeple provided a convenient landmark"

  • an event marking a unique or important historical change of course or one on which important developments depend

    同义词： turning point watershed

  • a mark showing the boundary of a piece of land
  • an anatomical structure used as a point of origin in locating other anatomical structures (as in surgery) or as point from which measurements can be taken

以上来源于: WordNet