The story
Borrowed from Kazakh тиын (tıyın) or Uzbek tiyin, тийин (tiyin), both originally meaning "squirrel", because in the ancient era squirrel pelts were used as currency. Compare Kazakh тиін (tiyin, “squirrel”), Kyrgyz тыйын (tıyın, “kopek, coin, squirrel”) Uyghur تىيىن (tiyin, “squirrel, kopeck”), dialectal Turkish teyin, Khakas тиин (tiin), Yakut тииҥ (tiiŋ), etc.
Etymology from Wiktionary, CC BY-SA 4.0.