Nile

The Nile (also known as the Nile River or River Nile) is an important river in Africa that flows northwards into the Mediterranean Sea. At roughly 6,650 km (4,130 mi) long, it is among the longest rivers in the world. Its drainage basin covers eleven countries: the Democratic Republic of the Congo, Tanzania, Burundi, Rwanda, Uganda, Kenya, Ethiopia, Eritrea, South Sudan, Sudan, and Egypt. It plays an important economic role in the economy of these nations, and it is the primary water source for South Sudan, Sudan and Egypt.

The Nile has two major tributaries: the White Nile and the Blue Nile. The White Nile, being the longer, is traditionally considered to be the headwaters, while the Blue Nile actually contributes 80% of the water and silt below the confluence of the two. The White Nile begins at Lake Victoria and flows through Uganda and South Sudan, while the Blue Nile begins at Lake Tana in Ethiopia and flows into Sudan from the southeast. The two rivers meet at the Sudanese capital of Khartoum.

After Khartoum the river flows north, almost entirely through the Nubian Desert, to Cairo and its large delta, joining the Mediterranean Sea at Alexandria. Egyptian civilization and Sudanese kingdoms have depended on the river and its annual flooding since ancient times. Most of the population and cities of Egypt lie along those parts of the Nile valley north of the Aswan Dam. Nearly all the cultural and historical sites of Ancient Egypt developed and are found along river banks. The Nile is, with the Rhône and Po, one of the three Mediterranean rivers with the largest water discharge.

In the ancient Egyptian language, the Nile is called Ḥꜥpy (Hapy) or Jtrw (Iteru), meaning "river". In Coptic, the word ⲫⲓⲁⲣⲟ, pronounced piaro (Sahidic) or phiaro (Bohairic), means "the river" (lit. p(h).iar-o "the-canal-great"), and comes from the same ancient name. In Nobiin, the river is called Áman Dawū, meaning "the great water". In Luganda, the river is called Kiira or Kiyira. In Runyoro, it is called Kihiira. In Egyptian Arabic, the Nile is called en-Nīl, while in Standard Arabic it is called an-Nīl. In Biblical Hebrew, it is הַיְאוֹר‎, Ha-Ye'or or הַשִׁיחוֹר‎, Ha-Shiḥor.

The English name Nile and the Arabic names en-Nîl and an-Nîl both derive from the Latin Nilus and the Ancient Greek Νεῖλος. Beyond that, however, the etymology is disputed. Homer called the river Αἴγυπτος, Aiguptos, but in subsequent periods, Greek authors referred to its lower course as Neilos; this term later became generalized for the entire river system. Thus, the name may derive from Ancient Egyptian expression nꜣ rꜣw-ḥꜣw(t) (lit. 'the mouths of the front parts'), which referred specifically to the branches of the Nile transversing the Delta, and would have been pronounced ni-lo-he in the area around Memphis in the 8th century BCE. Hesiod at his Theogony refers to Nilus (Νεῖλος) as one of the river gods, son of Oceanus and Tethys.

Another derivation of Nile might be related to the term Nil (Sanskrit: नील, romanized: nila; Egyptian Arabic: نيلة), which refers to Indigofera tinctoria, one of the original sources of indigo dye. Another may be Nymphaea caerulea, known as "The Sacred Blue Lily of the Nile", which was found scattered over Tutankhamun's corpse when it was excavated in 1922.^{[citation needed]} Another possible etymology derives from the Semitic term Nahal, meaning "river". Old Libyan has the term lilu, meaning water (in modern Berber ilel ⵉⵍⴻⵍ means sea).

With a total length of about 6,650 km (4,130 mi) between the region of Lake Victoria and the Mediterranean Sea, the Nile is among the longest rivers on Earth. The drainage basin of the Nile covers 3,254,555 square kilometers (1,256,591 sq mi), about 10% of the area of Africa. Compared to other major rivers, though, the Nile carries little water (5% of that of the Congo River, for example). The Nile basin is complex, and because of this, the discharge at any given point along the main stem depends on many factors including weather, diversions, evaporation and evapotranspiration, and groundwater flow.

Upstream from Khartoum (to the south), the river is known as the White Nile, a term also used in a limited sense to describe the section between Lake No and Khartoum. At Khartoum, the river is joined by the Blue Nile. The White Nile starts in equatorial East Africa, and the Blue Nile begins in Ethiopia. Both branches are on the western flanks of the East African Rift.