Abstrakt
The Sogdian language was once the lingua franca of the Silk Road. After the Arab invasion to Central Asia the language lost its prestige status and slowly diminished.
Since the Samanid Empire Persian became the prestigious language and later became a new lingua franca of the region. Sogdian or its dialects, however, did not disappear completely - at first it was an adstrate language in former Sogdiana, later it transformed into a substrate language, that was replaced by local Persian/Tajik vernacular(s) - these varieties of Persian are to be met in the Upper Zarafshon region North-Western Tajikistan.
The Upper Zarafshon (or Central) dialects of Tajik reflect many Eastern Iranian linguistic features that can be connected with vernaculars of Sogdiana such as Sogdian and its dialects and Yaghnobi, a language closely related to Sogdian. Eastern Iranian loans in the Central Tajik dialects show rather complicated linguistic situation in the mountainous parts of Sogdiana.
It seems, that the Upper Zarafshon Tajik dialects reflect a lost Sogdian dialect related to Yaghnobi, but having features of its own. The paper will show possibilities of study of the lost Sogdian dialect of the old Sogdian region of pyttmʼn/Buttamān.