fight-or-flight

American  

[fahyt-er-flahyt] / ˈfaɪt ərˈflaɪt /

adjective

1. causing, caused by, or being the body's physiological response to stress, involving the release of epinephrine and effects such as increased heart rate, blood pressure, and respiration, in preparation for self-defense or escape.

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noun

1. the fight-or-flight response or a situation that elicits it.

fight-or-flight British  

noun

1. (modifier) involving or relating to an involuntary response to stress in which the hormone adrenaline is secreted into the blood in readiness for physical action, such as fighting or running away

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Example Sentences

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

The softening of their features could be due to shifts in their fight-or-flight response on the cellular level, it says.

From BBC • Nov. 20, 2025

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

From Science Daily • Oct. 27, 2025

We assumed fight-or-flight positions, some of us crouching with fists raised like boxers, others like sprinters before the starting gun, though no one knew which way to run.

From "Hollow City" by Ransom Riggs