first-degree
adjective [ before noun ] US uk/ˌfɜːst.dɪˈɡriː/ us/ˌfɝːst.dɪˈɡriː/
一级的，最严重的（犯罪）
used to describe a crime that is the most serious of its type, especially because of being planned and intended
first-degree murder/felony/assault 一级谋杀/一级重罪/严重侵犯
Compare: second-degree