horrĭpĭlo

āre, v. n.

horreo-pilus

I. to bristle with hairs, be shaggy (post-class.): aures immodicis horripilant auctibus, App. M. 3, p. 140: horripilo ὀρθοτριχάω, horripilatur ὀρθοτριχεῖ, Gloss. Philox.
Lewis & Short
A Latin Dictionary, 1879
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