noradrenaline
/ˌnɔr əˈdrɛn əl ɪn/
noun
- A hormone and neurotransmitter released by the body in response to stress, which increases heart rate, blood pressure, and alertness, preparing the body for action. (Alternative spelling of noradrenalin.)
- The brain uses noradrenaline to help you stay focused during a test.
- A sudden loud noise can cause a spike in noradrenaline levels.
- Noradrenaline is often called the 'fight or flight' chemical.
Synonyms