Translation guide
The English word "reaction" covers a wide range of responses, from physical and chemical changes to emotional and social responses. In Japanese, different words and expressions are used depending on the context. This guide helps you choose the most natural Japanese equivalent.
Expressing how someone responds to something that happens or is said, often in a social or conversational context.
The most general and common word for "reaction." It can refer to physical, emotional, or social responses. Safe to use in most situations.
No one reacted to his joke.
Her reaction to the news was surprising.
A loanword from English, often used in casual conversation or entertainment contexts. It can imply a more visible or exaggerated response, like in TV shows.
He always has big reactions.
Refers specifically to verbal responses in a conversation, often implying a back-and-forth exchange. Used for how someone replies or handles questions.
Her responses are very polite.
Describing a scientific process where substances interact and change, or a physical response of the body.
Focusing on the emotional, psychological, or gut-level aspect of a reaction.
Still the most common word, but can be paired with emotional adjectives for clarity.
I had an emotional reaction to his words.
Means "reflex," used for automatic, instinctive physical or emotional responses.
Refers to how one takes or interprets something emotionally. More about the internal processing of an event.
Describing how a body or organism responds to a stimulus, drug, or treatment.
Expressing a negative response against change, progress, or a particular idea.
Means "opposition," "backlash," or "pushback." Used when people react negatively and resist something.
There was a backlash from employees against the new rules.
Means "reaction" in the sense of a counter-movement or rebound, often political or social.
Literally "rejection reaction," used for strong negative reactions, like rejecting a foreign idea or a transplant.
反応 is the standard, all-purpose word for "reaction." リアクション is a loanword that often implies a more exaggerated or performative response, like those seen on variety shows. In formal writing or serious contexts, stick with 反応.
In English, "reaction" is often used where Japanese would use a more specific verb or phrase. For example, "What was his reaction?" might be more naturally expressed as 「彼はどう思った？」 (What did he think?) or 「彼は何て言った？」 (What did he say?) depending on context.
I want to see his reaction.
She had an allergic reaction to the medicine.
The public reaction was mixed.
I had an allergic reaction.
Specifically means "chemical reaction." Use when you need to be precise.
Investigate the rate of the chemical reaction.
それは反射的な反応だった。
It was a reflex reaction.
People's reactions to criticism vary.
治療に対する応答は良好だった。
The response to treatment was good.
改革に対する反動が起きた。
There was a reaction against the reforms.
They showed a rejection reaction to his proposal.