The som, sum, or soum is a currency unit used in Turkic-speaking countries located in Central Asia. The name comes from words in the respective languages (including Kazakh, Kyrgyz, Tatar, Uyghur, and Uzbek) for "pure", referring to historical coins composed of pure gold.
The first som coin was a trough-shaped silver ingot from the Golden Horde in the 14th century. Centuries later, speakers of Kazakh, Kyrgyz, and Uzbek in the then Soviet Union referred to the ruble as the "som", and were accommodated by the word appearing on the reverses of banknotes. Currently, the som of Kyrgyzstan and the som of Uzbekistan are being circulated in their respective countries.