Translation guide
The English word "lethal" means capable of causing death. In Japanese, this concept is expressed through various words and phrases depending on whether you're talking about weapons, doses, injuries, or figurative situations. The most common and versatile equivalent is 致命的 (chimeiteki), but other options like 致死性 (chishisei) and 命取り (inochitori) are used in specific contexts.
Expressing that something is deadly or fatal, often used figuratively for flaws, mistakes, or problems.
The most common and versatile word for 'lethal' or 'fatal'. It can be used for physical threats (injuries, weapons) and figurative ones (mistakes, flaws). It is an adjective meaning 'fatal' or 'mortal'.
そのミスは致命的だった。
That mistake was lethal/fatal.
彼は致命的な傷を負った。
He suffered a lethal wound.
Literally 'life-taker', this noun is often used to describe a fatal flaw, mistake, or decision. It emphasizes the consequence of causing death or ruin.
その判断が命取りになった。
That decision proved lethal.
A technical or formal term meaning 'lethal' or 'fatal', often used in compounds like 致死量 (lethal dose). Not commonly used alone in everyday speech.
致死量の毒
a lethal dose of poison
Describing substances, doses, genes, or conditions that directly cause death.
A noun or adjective meaning 'lethality' or 'lethal nature'. Commonly used in medical and scientific contexts, e.g., 致死性の病気 (lethal disease).
これは致死性のウイルスです。
This is a lethal virus.
致死性の高い毒
a highly lethal poison
Used in compounds like 致死量 (lethal dose) or 致死率 (lethality rate). More technical than 致命的.
致死量を超える放射線
a lethal dose of radiation
A phrase meaning 'life-threatening' or 'lethal'. It is more colloquial than 致死性 and can be used in everyday conversation.
それは命に関わる病気です。
It's a lethal/life-threatening illness.
Describing weapons, strikes, or force that can kill.
Literally 'having killing/wounding power'. Used for weapons or attacks. More specific than 致命的.
殺傷力のある武器
a lethal weapon
Can also be used for weapons, e.g., 致死性の兵器 (lethal weapons), but is more technical.
致死性の兵器
lethal weapons
A formal/literary phrase meaning 'to cause death'. Used for describing the effect of an attack or weapon.
その一撃は彼を死に至らしめた。
The blow was lethal.
Describing something that causes ruin, failure, or severe damage, like a lethal combination or lethal effect.
Again, the most common choice for figurative lethality. 致命的な欠陥 (lethal flaw), 致命的な打撃 (lethal blow).
それは彼のキャリアに致命的な打撃を与えた。
It dealt a lethal blow to his career.
Means 'ruinous' or 'catastrophic'. Can be used when 'lethal' implies total destruction.
破滅的な結果
lethal consequences
致命的 (chimeiteki) is the most versatile and can be used in both physical and figurative contexts. 致死性 (chishisei) is more technical and often used in medical/scientific settings. 命取り (inochitori) is a noun that emphasizes a fatal flaw or mistake, often used in hindsight.
English uses 'lethal' as an adjective directly (lethal dose, lethal weapon). In Japanese, you often need to use a noun compound (致死量) or a relative clause (命に関わる). Simply saying リーサル is not natural outside of some loanword contexts (e.g., リーサル・ウェポン for the movie title).
その蛇の毒は致命的です。
The snake's venom is lethal.
彼は致命的なミスをした。
He made a lethal mistake.
この化学物質は人間にとって致死性があります。
This chemical is lethal to humans.