Different people often use different words to describe today's holiday. Some celebrate the opening of the New World to European exploration, while others celebrate (or lament) the first interaction between the Spaniards and (Native) Americans, and the civilization that developed as a result.
The name of this day of discovery also changes from one culture to another. Today is Columbus Day in the United States, but did you know that our American neighbors to the south celebrate the same holiday under different names? In Costa Rica, for example, The Day of the Cultures (El Día de las Culturas) paints a rosy picture of multiculturalism. In Mexico, The Day of the Races (El Día de la Raza) alludes to the mixing of Spanish and Indigenous cultures (and phenotypes) that is the foundation of Mexican civilization. In Venezuela, The Day of Indigenous Resistance (El Día de la Resistencia Indígena) glorifies the Pre-Columbian indigenous culture of the New World. (Learn more about Columbus Day.)
Today's Word of the Day, Neutral Ground, also deals with the collision between different societies, and may also mean a number of different things to different people.
I first learned this word as a New Orleans term for the median of city streets. As a former student of history, I loved the word's colonial origin as a meeting place for the French and the Spanish to trade.
Recently City Dictionary Citizens have taught us different meanings. For example, Neutral Ground is also one of the names for a territory in Western Louisiana that was disputed between Texas (then a part of Spain) and the United States, the latter of which recently gained adjacent territory in the Louisiana Purchase. To avoid confrontation, the two parties agreed to keep the strip of land neutral. The Neutral Ground was officially called the Sabine Free State, and has also been known by other names, including Neutral Strip, Neutral Territory, and No Man's Land (according to a Wikipedia article).
While we're talking about words colliding, some might mistakenly label Columbus as the man who proved the Earth was round. This simply isn't true. Eratosthenes, studying at the great library of Alexandria, discovered the roundness of the Earth in 240 BC and measured our planet's circumference with astonishing accuracy.
Here's an article that explains his discovery: http://www.wired.com/science/discoveries/news/2008/06/dayintech_0619
Here's Carl Sagan's story of Eratosthenes' work: http://www.youtube.com/watch?v=0JHEqBLG650
Maybe the average 15-century Spaniard thought the Earth was flat (and maybe even Fernando and Isabel themselves), but the winning argument had already been made available for nearly two millennia before Columbus set off for the Orient. Plus, he would have only proved the Earth was round (something that had already been done before) had he actually found the Orient by sailing west. Of course, we all know he came across something entirely different.