# activator

/ˈæktəˌveɪtɝ/ (US) · /ˈæktɪvˌeɪtɐ/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/activator
Updated: 2026-05-26

## Definition

a substance that starts a chemical reaction or makes a process happen faster. In biology, it can also be a protein that turns on a gene.

For teachers: a substance that initiates or accelerates a chemical reaction; in genetics, a protein that binds to DNA to increase the transcription of a specific gene.

## Examples

- In the mining industry, a chemical activator is often added to the water to help separate the valuable minerals from the waste rock.
- The research team identified a specific transcriptional activator that binds to the promoter region, effectively switching on the gene responsible for the plant's drought resistance.

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