noun
Mongolia; Greater Mongolia; Mongolian Plateau
Refers to the geographical region of Mongolia, often in historical or traditional contexts. Modern country is usually モンゴル.
蒙古は広大な草原地帯である。
Mongolia is a vast grassland region.
noun
Mongols; Mongol tribe
Historical term for the nomadic Mongol people. In modern usage, モンゴル人 is more common.
蒙古は13世紀に大帝国を築いた。
The Mongols built a great empire in the 13th century.
Modern term for Mongolia and Mongolian people; 蒙古 is more historical/literary.
From Chinese 蒙古 (Měnggǔ), a historical name for the Mongols. The exact origin of the Chinese term is uncertain.