An Etymological Dictionary of the German Language/Annotated/Lehne
Lehne (1.), feminine, ‘back or arm (of a chair), balustrade, railing,’ from the equivalent Middle High German lëne, line, feminine, Old High German lina, feminine, ‘reclinatorium’ for *hlina, which was probably the form in Gothic also. Compare Greek κλῖνη, ‘couch, mattress’ (these meanings also belong to Lehne in earlier Modern High German), and for further cognates see lehnen and Leiter.
Lehne (2.), feminine, from the equivalent Middle High German liene, with the remarkable variant liehe, feminine, ‘wild sow’; its further connection are difficult to determine; the similarity in sound with the equivalent French laie and Middle Latin lêfa (for lêha?) must not be overlooked. It is doubtful whether Lehne is of Teutonic origin.
Lehne (3.), feminine, ‘linch-pin’; compare Lünse.
Lehne (4.), Lenne, feminine, ‘Norwegian maple’; Middle High German and Old High German lîn-, lîmboum, hence also earlier Modern High German Leinbaum; the Modern High German form is borrowed from a Northern dialectic; Danish lön, Swedish lönn. Moreover the term was originally common to Teutonic; it was applied to the ‘maple’ in all the older dialects except Gothic; Old Icelandic hlynr, Anglo-Saxon hlyn (hlynn or hlîn?), and with these in the non Teutonic languages Slavonic klenŭ, and Lithuanian klévas, ‘maple,’ are primitively allied.