单词：pt 

名词

• 
  [1.n.pt] (同义词:[platinum( n. 白金, 铂 )]  [Pt([域] Portugal , 葡萄牙 )]  [atomic_number_78]  )
• 
  注释列句：a heavy precious metallic element; grey-white and resistant to corroding; occurs in some nickel and copper ores and is also found native in some deposits
• 上位词 -> [noble_metal(n.贵金属 )]  [metallic_element]  [chemical_element]  [substance( n. 物质, 实质, 主旨 )]  [matter( n. 事件, 问题, 物质, 内容, 实质, 原因, (印刷或书写的)文件, (文章或讲话等的)素材 vi. 有关系, 要紧 )]  [physical_entity]  [entity( n. 实体 )]