: 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.
For example, a person might intend to be courageous (cognition), but fear (affect) and a fight-or-flight response (physiology) can hinder action (behavior). Mary Crossan, Forbes, 20 Jan. 2025 But when the body’s fight-or-flight survival response doesn’t let up, temporary changes such as muscle tension, shallow breathing, rapid heartbeat and edginess can give way to headaches, trouble sleeping, irritability, and the debilitating paralysis symptomatic of chronic anxiety or depression. Sara Sidner, CNN, 19 Jan. 2025 What’s more, the development has tipped her over to Red Feather’s side of the fight-or-flight choice. Keith Phipps, Vulture, 10 Jan. 2025 This helps reduce the fight-or-flight response to stress and lowers cortisol levels, creating a feeling of safety and comfort. Mark Travers, Forbes, 7 Jan. 2025 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

Dictionary Entries Near fight-or-flight

Cite this Entry

“Fight-or-flight.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fight-or-flight. Accessed 27 Jan. 2025.

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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