单词：ac 

名词

• 
  [1.n.ac] (同义词:[actinium( n. [化]锕 )]  [Ac(=[拉] ante cibum 饭前(服) )]  [atomic_number_89]  )
• 
  注释列句：a radioactive element of the actinide series; found in uranium ores
• 上位词 -> [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 )] 
• 基本总称 -> [uranium_ore] 
  所有总称 -> [uranium_ore] 
  
• 
  [2.n.ac] (同义词:[alternating_current(n.交流电 )]  [AC(=[拉] ante cibum 饭前(服) )]  [alternating_electric_current]  )
• 
  注释列句：an electric current that reverses direction sinusoidally; "In the US most household current is AC at 60 cycles per second"
• 上位词 -> [electricity( n. 电流, 电, 电学 )]  [energy( n. 精力, 精神, 活力, [物]能量 )]  [physical_phenomenon]  [natural_phenomenon(自然现象 )]  [phenomenon( n. 现象 )]  [process( n. 过程, 作用, 方法, 程序, 步骤, 进行, 推移 vt. 加工, 处理 )]  [physical_entity]  [entity( n. 实体 )]