proper noun/a.muʁ/
The world's ninth longest river, forming the border between the Far East of Russia and Northeastern China, emptying into the Pacific Ocean through the Strait of Tartary, where the mouth of the river faces the northern end of the island of Sakhalin; an oblast in far eastern Russia; its administrative centre is Blagoveshchensk
Borrowed from Russian Аму́р (Amúr).