In its lower course the river is also known as the Kusak (Kazakh: Қусақ, Russian: Кусак, Chinese: 库萨克; pinyin: Kùsàkè).

Along most of its course, the river flows through the very sparsely populated mountainous terrain of the southern part of Xinjiang's Yumin County; by the time it crosses the China–Kazakhstan border and enters a flat desert east of Lake Zhalanashkol, its bed is usually dry, with little water ever reaching Lake Zhalanashkol.

According to topographic maps, the Terekty rises in the Kertau or Barlik (巴尔鲁克) Mountains at around 45°46′00″N 82°47′00″E / 45.76667°N 82.78333°E / 45.76667; 82.78333[1] After flowing to the south for some 20 km, and receiving several tributaries at around 45°39′00″N 82°46′00″E / 45.65000°N 82.76667°E / 45.65000; 82.76667, the Terekty turns west and flows in a narrow valley until it reaches the Alakol-Zhalanashkol depression.

Once entering the plain east of Lake Zhalanashkol at around 45°37′00″N 82°18′00″E / 45.61667°N 82.30000°E / 45.61667; 82.30000, the river forms a large alluvial fan.

"Terekty" is a fairly common place name in Kazakhstan, used (by itself or in combination with a modifier) for a number of villages, at least one other river,[2] and a mountain pass[2] elsewhere in the country.