pi·lo·erec·tion noun \ˌpī-lō-i-ˈrek-shən\
: involuntary erection or bristling of hairs due to a sympathetic reflex usually triggered by cold, shock, or fright or due to a sympathomimetic agent
Seen & Heard
What made you want to look up piloerection? Please tell us where you read or heard it (including the quote, if possible).