'hair-raising' originates from English, specifically combining the noun 'hair' and the present participle 'raising' (from the verb 'raise').

'hair' comes from Old English 'hær' and 'raise' comes via Old Norse 'reisa' (to raise) and Old French 'raiser'; the phrase developed in English as a literal description of hair being raised and later as a figurative adjective.

Initially, it meant 'causing the hair to stand up' (often literally); over time it evolved into the figurative meaning 'extremely frightening' or 'terrifying'.