untruth          
noun uk/ʌnˈtruːθ/ us/ʌnˈtruːθ/
 [ C ]瞎话;假话;谎言 
a statement that is not true
  It's not the first time that the paper has been in trouble for printing untruths about people's private lives. 这家报纸已经不是第一次因捏造人们私生活的新闻而惹上麻烦了。 
  [ U ]虚假;不真实 
the fact that something is not true
  The untruth of this statement was immediately clear to me. 我立刻就看出来这份声明是假的。