You're talking about the names of the continents
in English. In Chinese, all the continent names end in
zhou. Coincidence? Duh,
zhou is the Chinese word for "continent."
Europa and Asia were named by the ancient Greeks after female figures in their mythology. Female names end in A. Africa was named by the Romans, after the various peoples who called themselves
Afri. The ending
-ca is just a grammatical form meaning "country."
The rest of the continents were given Latin names by European scientists. Australia, from Latin
australis, "southern," with an A added to make it a noun. Since other Latin geographical names are feminine
(Britannia, Francia, Iberia, Germania, Italia, Scandinavia, China, India, Persia, etc.), they continued the tradition.
The continent at the south pole. Well, it should be named after the Latin word for "southern," so it would be Australia. Hmmm. Already used that one! Okay, how about Antarctica, from Greek
anti- and
arktikos, literally "the opposite of northern."
Arktos means "bear," as the constellation the Great Bear marks the north. In America with our charming homespun ways we call it the Big Dipper.
And America, named after Americus Vespucius, the Latinized form of Amerigo Vespucci, an explorer who came here after Columbus. Why Vespucci got two whole continents and a country named after him while Columbus only has the nation of Colombia and a District, is not clear. But since Columbus died believing that he'd found the eastern route to India and had named the indigenous people
indios, he's not exactly an authority.
America and Antarctica are pretty lame as names go. Perhaps there is a conspiracy.
BTW, we say Europe instead of Europa because we got the name from the Norman French when they conquered England in 1066. In French all those A's have been changed to silent E's:
Europe, Afrique, Asie, Australie, Amerique, Antarctique.