An Etymological Dictionary of the German Language/Annotated/Senkel
Senkel, masculine,‘plumb-line,’ from Middle High German sęnkel, masculine, ‘plumb-line, lace,’ also ‘anchor, drag-net,’ Old High German sęnchil, ‘anchor, drag-net.’ Allied to senken, Middle High German sęnken, Old High German sęnchen, ‘to lower’ (factitive of sinken; compare Old Saxon sęnkian, Gothic sagqjan, ‘to lower, let down’).