subterranean 

  1. 形容詞
地下的, 地中的
秘密的
隱藏的, 隱蔽的

    同義字詞
belowground,subsurface,underground

例句

  1. It was a subterranean structure.
  2. This would be the Subterranean Pass Way.
  3. He also introduced subterranean clover to Tasmania.
  4. There are hundreds of subterranean cages and mazes.
  5. The subterranean passages were used by coal trucks.