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The official language of Azerbaijan is Azerbaijani.
Azerbaijani or Azeri, also referred to as Azeri Turkic or Azeri Turkish, is a Turkic language from the Oghuz sub-branch spoken primarily by the Azerbaijani people, who live mainly in the Republic of Azerbaijan where the North Azerbaijani variety is spoken, and in the Azerbaijan region of Iran, where the South Azerbaijani variety is spoken.