America got its name from the explorer, Amerigo Vespucci.He was the navigator of the expedition that was the first to sight North America and the first to claim that Colubus had not encountered Asia, but a New World. His name was given to the "new World" by man named Walseemuller, who published Vespucci's accounts of the expedition.
La Merica was a star that supposedly marked the place of a perfect land that the Templars could prosper in after they had been "outlawed" in Europe. Its location was noted in some scrolls they claim were discovered under Herod's tomb. The Templars, therefore, would claim that America got its name from La Merica, but then again they claim an awful lot of silly things.