justifiable homicide
noun [ U ] law US uk/dʒʌs.tɪˌfaɪ.ə.bəl ˈhɒm.ɪ.saɪd/ us/dʒʌs.tɪˌfaɪ.ə.bəl ˈhɑː.mə.saɪd/
（尤指正当防卫时的）正当杀人
an act of killing someone that the law allows because it considers that there is a good reason for it, for example if you are defending yourself