单词：au 

名词

• 
  [1.n.au] (同义词:[gold( n. 黄金, 金币 adj. 金的, 金制的 )]  [Au( [域] Australia , 澳大利亚 )]  [atomic_number_79]  )
• 
  注释列句：a soft yellow malleable ductile (trivalent and univalent) metallic element; occurs mainly as nuggets in rocks and alluvial deposits; does not react with most chemicals but is attacked by chlorine and aqua regia
• 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 )] 
• 下位词 -> [24-karat_gold]  [gold_dust(n.砂金, 金粉 )]  [green_gold]  [guinea_gold] 
  基本总称 -> [dental_gold(镶牙金 )]  [sylvanite( n. [矿]针碲金银矿 )]  [gold_foil(n.金箔 )]  [gold_leaf(n.金叶 )]  [gold( n. 黄金, 金币 adj. 金的, 金制的 )] 
  所有总称 -> [dental_gold(镶牙金 )]  [sylvanite( n. [矿]针碲金银矿 )]  [gold_foil(n.金箔 )]  [gold_leaf(n.金叶 )]  [gold( n. 黄金, 金币 adj. 金的, 金制的 )] 
  
• 
  [2.n.au] (同义词:[Astronomical_Unit]  [AU( [域] Australia , 澳大利亚 )]  )
• 
  注释列句：a unit of length used for distances within the solar system; equal to the mean distance between the Earth and the Sun (approximately 93 million miles or 150 million kilometers)
• 上位词 -> [astronomy_unit]  [linear_unit]  [unit_of_measurement]  [definite_quantity(定量 )]  [measure( n. 尺寸, 量度器, 量度标准, 方法, 测量, 措施 vt. 测量, 测度, 估量, 分派, 权衡, 调节 vi. 量 )]  [abstraction( n. 提取 )]  [entity( n. 实体 )]