Language & WorldFact
"Sahara Desert" literally means "Desert Desert".
Sahara is Arabic for "deserts", Gobi is Mongolian for "desert". Such doublings arise when a name is borrowed from one language and the neighbours add the generic term again. England's River Avon is "River River" (Welsh afon), the Mississippi River is "Big-River River" (Algonquian), and Lake Chad is a "Lake Lake".
Useful: When you read a foreign place name, ask whether the generic word is already inside it.
Source: en.wikipedia.org