fight-or-flight

adjective

ˈfīt-ər-ˈflīt How to pronounce fight-or-flight (audio)
: relating to, being, or causing physiological changes in the body (such as an increase in heart rate or dilation of bronchi) in response to stress
epinephrine is a fight-or-flight hormone
a fight-or-flight reaction

Examples of fight-or-flight in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Short nights, dry cabin air, dehydration, alcohol, and caffeine all tip the body further towards fight-or-flight, leaving less room for recovery. — Anita Bhagwandas, Condé Nast Traveler, 31 Aug. 2026 Serotonin-norepinephrine reuptake inhibitors or SNRIs such as Cymbalta, Fetzima and Effexor XR prevent the reabsorption of serotonin and norepinephrine, which help shape the body’s fight-or-flight response. — Jen Christensen, CNN Money, 29 Aug. 2026 With it, Jack’s nervous system shifts easily into fight-or-flight mode. — Rebecca Noel, Charlotte Observer, 19 Aug. 2026 Manage Stress — Some stress is inevitable, but being in chronic fight-or-flight can speed up brain aging and inflammation build up. — Helen Carefoot, Flow Space, 14 Aug. 2026 See All Example Sentences for fight-or-flight

Word History

First Known Use

1973, in the meaning defined above

Time Traveler
The first known use of fight-or-flight was in 1973

Rhymes for fight-or-flight

See All Rhymes for fight-or-flight

Browse Nearby Words

fight one's way
fight-or-flight
fight shy of
See all Nearby Words

Cite this Entry

“Fight-or-flight.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fight-or-flight. Accessed 4 Sep. 2026.

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Medical Definition

fight-or-flight

adjective
ˌfī-tər-ˈflīt
: relating to, being, or causing physiological changes in the body (such as an increase in heart rate or dilation of bronchi) in response to stress
the fight-or-flight response
Last Updated: - Updated example sentences
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