: 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.
Your brain is hard-wired to zoom in on violence, mayhem and conflict for fight-or-flight purposes because those acts are threats to survival. Bryan Robinson, Forbes, 1 Nov. 2024 Epinephrine is a naturally occurring molecule in our bodies that is more commonly known as adrenaline, the hormone that regulates our fight-or-flight response. Marco Rubio, Newsweek, 1 Nov. 2024 Stress triggers a physical response known as the fight-or-flight response. Anna Giorgi, Verywell Health, 25 Oct. 2024 This chemical plays a key role in the fight-or-flight response by increasing heart rate, tightening blood vessels and boosting alertness—priming your brain and body to handle both physical and emotional challenges. Mark Travers, Forbes, 21 Oct. 2024 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 22 Nov. 2024.

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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