noun which may take the genitive case particle 'no', noun
A Sino-Japanese noun/no-adjective meaning that something causes or results in death. In practice it is especially common as the first element of compounds such as 致死量, 致死率, and 致死性.
致死量の薬物が体内から検出された。
A lethal dose of drugs was detected in the body.
この感染症は致死率が高い。
This infectious disease has a high fatality rate.
A more phrase-like expression meaning to lead to death; 致死 is a compact formal compound element.
A Sino-Japanese compound written with 致, associated here with bringing about or causing, and 死, death. The spelling directly reflects the idea of causing death.