An Etymological Dictionary of the German Language/Annotated/Säule
Säule (1.) (Bavarian Saul), feminine, ‘pillar,’ from the equivalent Middle High German sûl (plural siule), Old High German sûl (plural sûli), feminine; compare Dutch zuil, Anglo-Saxon sŷl; Old Icelandic súla, ‘pillar’; also, with gradation, Gothic sauls, feminine, ‘pillar.’ Perhaps Schwelle is primitively allied.
Säule (2.), feminine, ‘awl,’ from Middle High German siule, Old High German siula, feminine, ‘awl, punch’ (Gothic *siwila, feminine); connected with the Aryan root sī̆w, “the primitively word for leather-work” (see Ahle). Compare Gothic sinjan, Old High German siuwan, Anglo-Saxon seówian, English to sew; also Latin suo, ‘I sew,’ sutor, ‘cobbler,’ Greek κασ-σύω, ‘to patch, stitch,’ Sanscrit root sîw, ‘to sew,’ Old Slovenian ši-ti, ‘to sew.’ In a sense corresponding to that of Middle High German siule we find Latin subula and Old Slovenian šilo, which are formed from the same root. Compare the following word.