fight-or-flight reaction

American  

[fahyt-awr-flahyt] / ˈfaɪt ɔrˈflaɪt /

noun

Physiology, Psychology.

1. the response of the sympathetic nervous system to a stressful event, preparing the body to fight or flee, associated with the adrenal secretion of epinephrine and characterized by increased heart rate, increased blood flow to the brain and muscles, raised sugar levels, sweaty palms and soles, dilated pupils, and erect hairs.

---

fight or flight reaction Cultural  

1. The set of processes that occur in the body when it is confronted with some form of physical or mental stress. For example, if a person is faced with danger (as from a vicious animal about to attack), the nervous system signals for adrenaline and other hormones to be released into the blood. These hormones prepare the body either to confront the attacking animal or to flee to safety (thus, “fight or flight”). Changes in the body include increased heart rate, dilated pupils of the eye (to improve vision), and increased supply of blood to the muscles (to prepare the body for action).

---

Example Sentences

Fear can generate a fight-or-flight reaction, but it’s ultimately counterproductive.

From Seattle Times • Feb. 9, 2024

As for what’s happening in the body, Kaufman speculated it was a mini fight-or-flight reaction — that when the small particles entered someone’s lungs or bloodstream, the body would perceive them as a threat.

From Seattle Times • Nov. 30, 2023

Your brain's amygdala becomes more active, which controls your innate fight-or-flight reaction when you feel under threat.

From Salon • Aug. 14, 2022

You may find you have a fight-or-flight reaction to running.

From Seattle Times • Sep. 1, 2020

To Davis, the darkness stirs a fight-or-flight reaction.

From The Guardian • Oct. 21, 2016