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fight-or-flight response

Scientific  
/ fītôr-flīt /
  1. A physiological reaction in response to stress, characterized by an increase in heart rate and blood pressure, elevation of glucose levels in the blood, and redistribution of blood from the digestive tract to the muscles. These changes are caused by activation of the sympathetic nervous system by epinephrine (adrenaline), which prepares the body to challenge or flee from a perceived threat.


Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

That’s our fight-or-flight response at work, and it can cause a lot of problems in a relationship.

From The Wall Street Journal

Vd Roest was well aware that the man’s virtually generated image wasn’t real, but that didn’t stop a fight-or-flight response from kicking in upon seeing his face.

From Slate

For example, norepinephrine, a chemical involved in the body's "fight-or-flight" response, is often higher than normal in anxiety disorders.

From Science Daily

She felt locked in a fight-or-flight response.

From The Wall Street Journal

The softening of their features could be due to shifts in their fight-or-flight response on the cellular level, it says.

From BBC