An Etymological Dictionary of the German Language/Annotated/Lümmel

by Friedrich Kluge

Lümmel, masculine, ‘lubber, scoundrel,’ first occurs in Modern High German; probably derived from the antiquated adjective lumm, ‘relaxed, loose,’ which is based on Middle High German lüeme, Old High German luomi, ‘mild, languid’ (Middle High German lüemen, ‘to slacken, relax, be wearied’), and connected with lahm.