: 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

Example Sentences

Recent Examples on the Web When our bodies are under stress, either physical (like an injury) or psychological (like relationship struggles), our bodies go through an intense hormonal and neurological response – most commonly known as the fight-or-flight reflex. Delaney Nothaft, USA TODAY, 24 May 2023 That particular sequence provides a good early test of your fight-or-flight instincts. Justin Chang, Los Angeles Times, 27 Apr. 2023 Our cognitive system responds to pressures with a process called allostasis, which senses threats to our well-being and fires off fight-or-flight responses to disarm them. Gabriela Riccardi, Quartz, 21 Apr. 2023 When you’re stressed, your body gets ready to enter fight-or-flight mode. Addison Aloian, Women's Health, 21 Apr. 2023 An increased sense of fight-or-flight. Delaney Nothaft, USA TODAY, 19 Apr. 2023 Long-term stress can mean our fight-or-flight response does its thing on a hair trigger. Eleanor Morgan, refinery29.com, 12 Apr. 2023 Cortisol is a stress hormone that can appropriately raise sugar in the bloodstream, help convert glucose to energy, and assist in fight-or-flight situations.1 Cortisol is produced and regulated in adrenal glands located near the top of the kidneys. Cathy Cassata, Health, 12 Apr. 2023 According to Viega, his adolescent patients in North Philadelphia and South Chicago often lived in sound environments filled with sirens and other noises that trigger a fight-or-flight response. Claire Bugos, Verywell Health, 6 Apr. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'fight-or-flight.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

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 4 Jun. 2023.

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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