fight-or-flight
adjective
: 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
Instead of recognizing the tumor as an invader that needs to be destroyed, the brain processes the signal and activates the sympathetic nervous system, mainly known as the driver of the fight-or-flight response.
—
Jacek Krywko, Scientific American, 4 Feb. 2026
Glenn described how adrenaline can hijack her system, pushing her into a constant fight-or-flight state.
—Marcus Thompson Ii, New York Times, 4 Feb. 2026
Neuroscience teaches us that under conditions of danger, the brain’s instinctive response is often to amplify the perception of threat as a default fight-or-flight mechanism for survival.
—Laurence Miller, Sun Sentinel, 14 Jan. 2026
Under chronic stress, however, the nervous system remains biased toward fight-or-flight, even when no immediate danger is present.
—Dana Santas, CNN Money, 14 Jan. 2026
See All Example Sentences for fight-or-flight
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Jacek Krywko, Scientific American, 4 Feb. 2026
Glenn described how adrenaline can hijack her system, pushing her into a constant fight-or-flight state.
—Marcus Thompson Ii, New York Times, 4 Feb. 2026
Neuroscience teaches us that under conditions of danger, the brain’s instinctive response is often to amplify the perception of threat as a default fight-or-flight mechanism for survival.
—Laurence Miller, Sun Sentinel, 14 Jan. 2026
Under chronic stress, however, the nervous system remains biased toward fight-or-flight, even when no immediate danger is present.
—Dana Santas, CNN Money, 14 Jan. 2026
See All Example Sentences for 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 18 Feb. 2026.
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