unconcern /ˌʌnkənˈsɜːn/ TEM4

• 1. 

  N-UNCOUNT A person's unconcern is their lack of interest in or anxiety about something, often something that most people would be concerned about. 不感兴趣; 不关心

  例：

  She'd mentioned it casually once, surprising him by her unconcern.

  她随意地提过一次这个事，她的漠不关心让他吃惊。