An Etymological Dictionary of the German Language/Sieg
Sieg, m., ‘victory, triumph, conquest,’ from the equiv. MidHG. sige, also sic (g), OHG. sigi, sigu, m.; a common Teut. word; comp. Goth. sigis, OIc. sigr, AS. segor and sige, Du. zege. The great antiquity of the Teut. stem segoz, sigiz, is attested both by the proper names Segi-mêrus, Segi-mundus, and Segestes, mentioned by Tacitus, and by the terms in the cognate languages; Aryan séghos, n., ‘prevailing might,’ is implied also by Ind. sáhas and Zend hazaṅh, ‘power, might, victory.’ Comp. Sans. sah, ‘to overpower, vanquish, conquer,’ to which Gr. ἔχω (aor. ἔ-σχ-ον) and OIr. segaim, ‘I attain,’ are closely allied.