I've seen many regions that use the name Columbia, but what does it mean? What's its origin?
Answer from a Native speaker
In the American context, "Columbia" is the name of a district that was named after Christopher Columbus, the Italian explorer who triggered the colonization process of the "New World" (which later became the United States and Canada) starting in the 15th century. In addition to the settlement and colonization of these Northern areas (which are known now as North America), Europeans also settled and colonized lands down south. One of these places became known as Colombia later. Colombia, a country in the northern part of South America, is another place named after Christopher Columbus. You can assume that any place with this name in the Americas is named after him.