lassitude
/ˈlæsɪtjuːd/noun
mass noun
- a state of physical or mental weariness; lack of energy疲乏, 疲倦; 无力：
she was overcome by lassitude and retired to bed
她疲倦得不行, 上床休息了
a patient complaining of lassitude and inability to concentrate.
一位自诉疲乏而且不能集中精力的病人。
词源
late Middle English: from French， from Latin lassitudo, from lassus 'tired'.