An Etymological Dictionary of the German Language/Annotated/Garn
Garn, neuter, ‘yarn, thread, net, snare,’ from the equivalent Middle High German and Old High German garn; corresponding to Anglo-Saxon gearn, English yarn, Old Icelandic garn, neuter, Dutch garen; the common Teutonic term for ‘yarn’ (Gothic *garn, neuter); the meaning ‘net’ was attached to Garn, even in the Old High German and Middle High German period, but it never obtained in English and Scandinavian. We might assume a root gar with some such meaning as ‘to turn,’ but it is not authenticated. Earlier Teutonic has a series of terms corresponding in sound with Garn and meaning ‘entrails’; compare Old Icelandic gǫrn (plural garner), feminine, ‘gut, intestines, entrails,’ Old High German mittigarni, mittilagarni, neuter, ‘fat found in the middle of the entrails, arvina,’ Anglo-Saxon micgern (cg for dg; compare Anglo-Saxon orceard, English orchard, for ortgeard), ‘arvina’ These words have been connected with Lithuanian żarnà, feminine, ‘gut,’ and Sanscrit hirâ, feminine, ‘gut,’ though the latter may be allied to Latin hîra, feminine, ‘gut,’ and hilla for hirla; likewise Latin haru- in haru-spex, ‘one who examines the entrails, soothsayer,’ and hariolus, ‘soothsayer,’ contain the Aryan root ghar. Perhaps — and nothing further can be sail — all the words discussed above are based on a Teutonic root ghar, ‘to turn.’