单词：laboriousness 

名词

• 
  [1.n.laboriousness] (同义词:[laboriousness]  [operoseness]  [toilsomeness]  )
• 
  注释列句：the quality of requiring extended effort
• 上位词 -> [effortfulness]  [difficulty( n. 困难, 难点 )]  [quality( n. 质量, 品质, 性质 )]  [attribute( n. 属性, 品质, 特征, 加于, 归结于 )]  [abstraction( n. 提取 )]  [entity( n. 实体 )] 
• 派生词 -> [laborious( adj. (指工作)艰苦的, 费力的, (指人)勤劳的 )]