Believe it or not, the Oxford English Dictionary can be very useful for sketching out the general form of these things. As it goes, "Indies" were the general region surrounding India, when European explorers like Columbus were going westward, their thoughts were to India. Of course that dream was quickly cut short, as those who followed realized that these Indies were not the same Indies that had brought traders glory through cloves, nutmeg, cinnamon, and pepper. The American continent formed a kind of great wall from the Arctic to Tierra del Fuego. In 1513 Vasco Núñez de Balboa would cross Panama and got a sight of the Pacific Ocean, but whatever responses this news elicited, it was not a renaming of those American islands. The "West" and "East" are relative to the trading capitals in Europe, but in English the "Indies," whether the Caribbean or Malay Archipelago, basically stuck around as misnomers often do. But not everyone kept up the conflation between the Caribbean and South East Asia---for the Spanish the region would become known as the Antilles, with French, Portuguese, and Dutch having their variation on this geographical name.