An Etymological Dictionary of the German Language/Annotated/Schnecke
Schnecke, feminine, ‘snail, slug, spiral staircase,’ from Middle High German snëcke, masculine, ‘snail, tortoise, spiral staircase,’ Old High German snëcko, masculine, ‘snail’; corresponding to Low German snigge (Gothic *snigga, masculine, is wanting). Gothic *snagils is implied by Middle High German snęgel, Modern High German (Hessian) Schnegel, ‘snail,’ Low German snagel, Anglo-Saxon snœgel, English snail. Compare further Old Icelandic snigell.