piloerection

noun

pi·​lo·​erec·​tion ˌpī-lō-i-ˈrek-shən How to pronounce piloerection (audio)
: erection or bristling of hairs due to the involuntary contraction of small muscles at the base of hair follicles that occurs as a reflexive response of the sympathetic nervous system especially to cold, shock, or fright

Note: Piloerection may also occur as a side effect from the use of a sympathomimetic drug (such as phenylephrine) or as a symptom of opioid withdrawal.

Examples of piloerection 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.
Animals typically deploy their morphology during conflict to enhance competitors' assessments of their fighting ability (e.g. bared fangs, piloerection, dewlap inflation). Seriously Science, Discover Magazine, 9 Sep. 2014

Word History

Etymology

Latin pilus "hair" + -o- + erection

First Known Use

1930, in the meaning defined above

Time Traveler
The first known use of piloerection was in 1930

Dictionary Entries Near piloerection

Cite this Entry

“Piloerection.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/piloerection. Accessed 22 Dec. 2024.

Medical Definition

piloerection

noun
pi·​lo·​erec·​tion ˌpī-lō-i-ˈrek-shən How to pronounce piloerection (audio)
: erection or bristling of hairs due to the involuntary contraction of small muscles at the base of hair follicles that occurs as a reflexive response of the sympathetic nervous system especially to cold, shock, or fright

Note: Piloerection may also occur as a side effect from the use of a sympathomimetic drug (as phenylephrine) or as a symptom of opioid withdrawal.

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