# react

/ɹiˈækt/ (US) · /ɹɪˈækt/ (UK)

Source: https://englishreference.com/word/react
Updated: 2026-06-19

## Senses

### 1. to respond to something

verb · CEFR A2

to change your behaviour or feelings because of something that happens.

For teachers: to act in response to a stimulus, event, or situation. Intransitive; typically takes the preposition 'to'.

- How did your parents react when you told them you were moving?
- The markets reacted sharply to the central bank's announcement, with stock prices falling within minutes of the press conference.

### 2. chemical change

verb · CEFR B2 · Technical

to change when mixed with another substance.

For teachers: to undergo a chemical change when in contact with another substance or energy source. Often used with 'with'.

- The acid will react with the metal and create small bubbles.
- When the two compounds react under high pressure, they form a stable polymer that is resistant to heat.

### 3. social media response

verb · CEFR B1 · Informal

to use an emoji or icon to show how you feel about a post online.

For teachers: to post a digital reaction, such as an emoji, to indicate a specific emotional response to a message or post.

- I didn't have time to reply, so I just reacted with a heart emoji.
- Users can now react to individual messages in the thread, allowing for quicker feedback without cluttering the conversation with text.

### 4. an emoji response

noun · CEFR B2 · Slang · Informal

an emoji or icon used to show a feeling on social media.

For teachers: a specific emoji or symbolic icon selected by a user to express a sentiment toward a digital post.

- The post got over a hundred likes and several angry reacts.
- The community manager noted that the 'laugh' react was being used sarcastically on the company's official announcement.

## Examples

- How did she react when you told her the news?
- The skin may react to the new cream if you have sensitive allergies, so test a small area first.
- Investors tended to react unpredictably to the central bank's announcement, causing the market to fluctuate wildly before stabilizing late in the afternoon.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.