ruthlessness       
noun [ U ] uk/ˈruːθ.ləs.nəs/ us/ˈruːθ.ləs.nəs/
 无情;冷酷;残忍
the quality of not thinking or worrying about any pain caused to others when deciding what you need to do
  He behaved with utter ruthlessness. 他表现得极其冷酷无情。 
 There was a certain ruthlessness about her. 她有些冷酷无情。 
 See: ruthless
 - More examples
- I question whether he has the ambition or the ruthlessness to succeed as chairman.
- Had the home side displayed such ruthlessness in front of goal, they might have won.
- This shows the ruthlessness that has kept her at the top.