An Etymological Dictionary of the German Language/Annotated/Letten

by Friedrich Kluge

Letten, masculine ‘(potter's) clay,’ from Middle High German lëtte, Old High German lëtto, masculine, ‘loam’ (ë is due to the Bavarian and Alemannian dialects); to this is probably allied the Icelandic graded form leþja, ., ‘loam, dirt.’ It is connected by some etymologists with Latin lŭtum, neuter, ‘mud, dirt,’ and by others, less probably, with Old Prussian laydis, ‘loam,’ whose diphthong, compared with the a of the Teutonic word, presents a difficulty.