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.
Locals and tourists calling Luna’s name or chasing her trigger her fight-or-flight response and drive the dog further into the park, Boucher said. — ABC News, 14 Oct. 2026 With that much pulse-pounding, fight-or-flight-revving goodness, maybe there should be a law. — Sara Netzley, Entertainment Weekly, 11 Oct. 2026 Very deep or uncomfortable pressure can do the opposite and push the body into a fight-or-flight response. — Samantha Agate, Kansas City Star, 1 Oct. 2026 The video starts with a discussion of fight-or-flight and other autistic behaviors, which appear when a student feels physically unsafe or — something that is much harder for a neurotypical person to anticipate — socially unsafe. — Beth Hawkins, Denver Post, 15 Sep. 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 23 Oct. 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
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