An Etymological Dictionary of the German Language/Annotated/Leine
Leine, feminine, ‘line,’ from Middle High German and Middle Low German lîne, feminine, late Old High German lîna, feminine, ‘rope, cable, line,’ especially ‘towline.’ The derivation from Latin lînea is doubtful, because the latter does not signify ‘cable’ even in Middle Latin but specially ‘plumb-line,’ and in Middle Latin ‘measure of length.’ As far as the sense is concerned, the word is more closely connected with Latin lînum, ‘thread, cable, rope’; hence Old High German lîna is the plural of the Latin word. In Romance and Middle Latin, however, lînum does not occur in this sense. Perhaps Leine, as an independent Teutonic derivative of lîn, ‘linen,’ corresponds to Greek λιναία, λινέα, ‘rope, cord’?. In that case Anglo-Saxon lîne, English line, and Old Icelandic lína (Gothic *leinjô, literally ‘what is prepared from flax’), are also formed according to the genuinely Teutonic principle (suffix, jôn).