形容詞 nerveless:

1. marked by calm self-control (especially in trying circumstances); unemotional
   同義詞：cool, coolheaded
2. lacking strength- Nathaniel Hawthorne
   同義詞：feeble

1. The knife fell from her nerveless fingers.
   刀子從她那無力的手中落下。

nerve.less

adj.（形容詞）
Lacking strength or energy; spiritless; weak.
無力的：無力或無精力；無精打彩的；虛弱
Lacking courage; spineless or cowardly.
無勇氣的：缺乏勇氣的；懦弱的或膽小的
Calm and controlled in trying circumstances; cool.
冷靜的：在逆境中平靜且能自控；冷靜的

【引伸】
nerve.lessly
adv.（副詞）
nerve.lessness
n.（名詞）