The story
From Medieval Greek Ταυγάστ (Taugást) or Ταυγάς (Taugás). Its origin is debated; theories include derivation from the Tuoba (拓跋) clan or from 大漢 /大汉 (Dàhàn, “Great Han”), an ancient appellation for dynasties in the region.
Etymology from Wiktionary, CC BY-SA 4.0.