Which major African river's name means "Great River" in the local Tonga dialect?

The source of the mighty Zambezi River lies at about 1 500 m (4 900ft) above sea level in the Mwinilunga District, very close to the border where Zambia, Angola and the Congo meet.

From there it flows through Zambia, Angola, Namibia and Botswana then back along the border of Zambia and Zimbabwe finally discharging into the Indian Ocean at its delta in Mozambique. The area of its catchment basin is 1 390 000 square km which is half that of the Nile.

It is thought Zambezi means ‘Great River’ in the language of the Tonga people who inhabit its middle reaches. However the Lozi refer to the river as 'yambezhi' (pronounced 'le-am-by'), meaning 'heart of all', but it is possible the name has common ancestory in both languages.

For many years the river was spelt 'Zambesi', with the now popular spelling of 'Zambezi' becoming only widely used in the latter half of the last century.