na-adjective
Used as a na-adjective to describe something that is fatal, often in medical, accident, or metaphorical contexts. Less common than native equivalents like 致命的 (ちめいてき).
その事故は彼にとってフェータルな結果をもたらした。
The accident had fatal consequences for him.
このバグはシステムにとってフェータルな問題だ。
This bug is a fatal problem for the system.