An Etymological Dictionary of the German Language/Borste
Borste, f., ‘bristle,’ from the equiv. MidHG. borste, f., bürst, borst, m., n., OHG. burst, m., n.; comp. AS. byrst, and with a suffix l, brystl, E. bristle; Goth. *baúrstus or *baúrsts, f., is not recorded. Bors- is the Teut. form of the root; comp. further E. bur, from AS. *burr (for *burzu-, properly ‘bristly’). Pre-Teut. bhers- shows itself in OInd. bhṛš-ṭi-, ‘point, prong, corner’; also in Lat. fastigium, ‘extreme edge’?. Comp. Bürste.