An Etymological Dictionary of the German Language/Annotated/Eisen

by Friedrich Kluge

Eisen, neuter, ‘iron, weapon, sword, fetters,’ from Middle High German and Middle Low German îsen (îsern), Old High German îsan, îsarn, neuter, ‘iron’; corresponds to Dutch ijzer, Anglo-Saxon îsern, îren, English iron, Old Icelandic ísarn, Gothic eisarn, ‘iron.’ Its relation to Eis is still undecided; it is most closely connected with Old Irish íarn, ‘iron’ (for *ísarno-), whence Old Icelandic jarn (Danish jern) is borrowed. It is less certain that Old High German êr, Gothic aiz, Latin aes, ‘bronze,’ are allied to it. The derivative r of the earlier forms is retained by Modern High German eisern, which is based on Middle High German îserîn, îsernîn, Old High German îsarnîn, adjective, ‘of iron.’