An Etymological Dictionary of the German Language/zwingen
zwingen, vb., ‘to force, compel, vanquish,’ from MidHG. twingen, dwingen, ‘to press, cramp, force, compel, dominate,’ OHG. dwingan, thwingan, ‘to crowd, suppress, conquer,’ corresponding to OSax. thwingan, OIc. þwinga, Dan. tvinge, Du. twingen, OFris. dwinga, twinga, MidE. twingen, ‘to force’ (E. twinge), see also Zwang. — Derivatives Zwing, Twink, m., ‘fortress,’ from MidHG. twine, m., ‘that which constrains, confines; jurisdiction.’ —