piloerection

noun pi·lo·erec·tion \ ˌpī-lō-i-ˈrek-shən \

Definition of piloerection

: 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.

Origin and Etymology of piloerection

Latin pilus "hair" + -o- + erection


Medical Dictionary

piloerection

noun pi·lo·erec·tion \ ˌpī-lō-i-ˈrek-shən \

medical Definition of piloerection

: involuntary erection or bristling of hairs due to a sympathetic reflex usually triggered by cold, shock, or fright or due to a sympathomimetic agent

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