An Etymological Dictionary of the German Language/Annotated/säumen
säumen, verb, ‘to linger,’ from Middle High German sûmen, ‘to stay, defer, loiter, linger’; Old High German only virsûmen (Middle High German versûmen), ‘to let slip,’ and ar-sûmen, ‘to omit.’ The history of the word is very obscure, because it is peculiar to German, and appears only in a compound form in Old High German. The great antiquity of the compound is attested by Middle High German frá-sûme, masculine, ‘delay,’ which points to Gothic *frá-sûma, masculine; we should have expected Middle High German versûme. Probably the meaning, which properly belongs only to the compound, has been transferred to the simple form. —