defective       
adjective uk/dɪˈfek.tɪv/ us/dɪˈfek.tɪv/
C2 有缺陷的,有毛病的,有问题的
Something that is defective has a fault in it and does not work correctly.
  defective brakes 有问题的制动装置 
 defective eyesight 有缺陷的视力 
 a defective gene 缺损的基因 
 I think that theory is defective. 我认为那种理论有缺陷。