Blue Nile
noun
a river in E Africa, flowing NNW from Lake Tana in Ethiopia into the Nile at Khartoum: a tributary of the Nile. About 950 miles (1530 km) long.
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British Dictionary definitions for blue nile
Blue Nile
noun
a river in E Africa, rising in central Ethiopia as the Abbai and flowing southeast, then northwest to join the White Nile. Length: about 1530 km (950 miles)