By hovering over the names, you will see the actual country's name and other possible etymologies.
This map was inspired by this etymological map of the USA. It does not claim to be exact; etymology is not an accurate science. 18th and 19th century armchair historians, geographers and linguists wrote countless books to explain the etymology of place names. Their idea was to explain the origin of Africans by tracing African languages back to a certain part of the world. The most famous example was the Hamitic hypothesis - if a toponym could be linked with Ham, son of Noah, it meant that an ethnic group in particular came from Egypt or the Middle East. This map is clearly not an attempt to revive endless debates on the pseudo-origin of peoples as it is pretty easy to see how these theories have led to scientific racism. For a discussion of these issues see this article.
This map aims at showing the variety of names used to designate African countries in modern English. The effect of this translation is to level all historical, geographical and linguistic differences between every country. The names and definitions were often copied and pasted from this page on Wikipedia, so, it goes without saying, that this map is not the result of any in-depth research. If you think that some of my translations are incorrect or could be improved, please contact me. Obviously, this is quite an artificial exercise. I don't know if someone has noticed but the word "black" comes back quite often... Among other possibilities, "Africa" could mean "Sunny Land" - so on this map, "South Africa" appears as "Southern Sunny Land". South Africa was not named after its climate but after its geographic location. So, yes to a certain extent, this map doesn't make any sense.
Under a more historical angle, countries such as Burkina Faso chose to be called in 1984 the "land of Honest Men" as it was known under the colonial name of "Upper Volta" before. Choosing to get rid of the colonial past by using African languages was thus seen as a logical step by some African countries (Mali, Benin or Ghana did exactly the same). That's why place names can be excellent primary sources to understand history at different scales. The fact that competing etymologies still exist nowadays can tell us a lot about postcolonial Africa. For example, why do we have so many possible etymologies for Niger? It seems that modern political situations still largely influence linguistic debates on the origin of these toponyms. See this comparison between Southern Senegambia and Germany to see the potential of such an approach.
It is always quite difficult to find a good projection for African maps. Most projections used in the media tend to distort African distances. The Chamberlin trimetric projection is clearly a compromise between area, direction and distance. It is constructed by triangulating three base points (22°N, 0°), (22°N, 45°E), (22°S, 22.5°E). It was first built by Chamberlin in 1947 and was adapted to d3.js by Jason Davies. For an explanation on why we should change projections according to the scale of the map, see this page.