third-degree
adjective /ˌθɜːd dɪˈɡriː/
  /ˌθɜːrd dɪˈɡriː/
 - third-degree burns burns of the most serious kind, affecting tissue below the skinTopics Illnessc2
 - (North American English) third-degree murder, assault, robbery, etc. murder, etc. of the least serious of three kinds compare first-degree, second-degree