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alarm reaction

noun Physiology.

the first stage of the general adaptation syndrome, in which the body responds to stress by exhibiting shock.

Origin of alarm reaction

First recorded in 1935–40
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
alarm reaction in Medicine

alarm reaction

[ə-lärm′]

n.

The initial stage in the body's response to stressful stimuli, characterized by adaptive physiological changes, such as increased hormonal activity and increased heart rate.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.