Translation guide
The English verb 'worsen' means to become worse or to make something worse. In Japanese, the expression depends on whether the change is natural or caused, and on the formality of the situation.
To describe a situation, condition, or state that deteriorates on its own.
The most common and neutral way to say 'worsen' for conditions, situations, health, relationships, etc. Used in both spoken and written Japanese.
彼の病状が悪化した。
His condition worsened.
天候が悪化してきた。
The weather is worsening.
To describe an action that causes something to deteriorate.
The standard transitive form of 悪化する. Used when someone or something causes a situation to worsen.
その政策が状況を悪化させた。
The policy worsened the situation.
悪化する is the most neutral and widely used for both formal and informal situations. ひどくなる is more colloquial and often implies a subjective sense of severity (e.g., pain, weather). 悪くなる is simple and direct but can sound slightly childish or blunt in formal contexts. For transitive uses, 悪化させる is the standard, while ひどくする and 悪くする are casual.
English 'worsen' is often translated as a phrase in Japanese. Using a single verb like 悪化する is natural, but learners sometimes try to force a direct equivalent. Remember that intransitive/transitive pairs are distinct in Japanese.
A more casual, everyday expression meaning 'to get worse'. Often used for pain, weather, or personal situations.
痛みがひどくなった。
The pain worsened.
雨がひどくなってきた。
The rain is getting worse.
Literally 'to become bad'. Simple and common, but slightly less formal than 悪化する. Suitable for everyday conversation.
状況が悪くなった。
The situation worsened.
Means 'to become serious/severe'. Used for problems, crises, or situations that escalate in severity. More formal and often used in news or reports.
紛争が深刻化している。
The conflict is worsening.
Stress can worsen symptoms.
Casual transitive form of ひどい. Used in everyday speech when someone makes something worse.
彼の一言が事態をひどくした。
His one remark worsened the situation.
Simple transitive form meaning 'to make bad/worse'. Common in casual contexts.
そんなことをしたら事態を悪くするだけだ。
Doing that will only worsen the situation.
Transitive form of 深刻化する. Used in formal contexts when someone or something makes a problem more serious.
その発言が対立を深刻化させた。
The statement worsened the conflict.