isarnodori

iron, Irish iarann, Middle Irish iarund, Old Irish iarn, Welsh haiarn, hearn, Cornish hoern, Old Breton hoiarn, Breton houarn, Gaulish isarnodori, ferrei ostii: *eisarno-; Gothic eisarn, Old High German isarn, German eisen, English iron (all borrowed from Celtic according to Brugmann, Stokes, etc.). Shräder regards the eis or îs of eisarno- as only a different vowel-scale form of Indo-European ayos, ayes-, metal, whence Latin aes, English ore.