fight-or-flight response

American  

[fahyt-er-flahyt-ruh-spahns] / ˈfaɪt ərˈflaɪt rəˌspɑns /

noun

plural

fight-or-flight responses

1. Physiology. the body's response to stress, involving the release of epinephrine and effects such as increased heart rate, blood pressure, and respiration.

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fight-or-flight response Scientific  

/ fīt′ôr-flīt′ /

1. A physiological reaction in response to stress, characterized by an increase in heart rate and blood pressure, elevation of glucose levels in the blood, and redistribution of blood from the digestive tract to the muscles. These changes are caused by activation of the sympathetic nervous system by epinephrine (adrenaline), which prepares the body to challenge or flee from a perceived threat.

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Example Sentences

Wass says this kind of content creates a fight-or-flight response in a child's brain.

From BBC • Mar. 27, 2026

That’s our fight-or-flight response at work, and it can cause a lot of problems in a relationship.

From The Wall Street Journal • Dec. 27, 2025

Vd Roest was well aware that the man’s virtually generated image wasn’t real, but that didn’t stop a fight-or-flight response from kicking in upon seeing his face.

From Slate • Dec. 18, 2025

Persistent worry activates the body's fight-or-flight response, triggering stress hormones that cause physical effects.

From Science Daily • Oct. 27, 2025

I wonder if after a while your body starts to wear down when you don’t listen to that fight-or-flight response.

From "Internment" by Samira Ahmed