In many cases, people tend to use the terms “race” and “ethnicity” interchangeably. At other times, they use “ethnicity” as another word for “national origin.” Neither of this is a correct usage as far as the social sciences are concerned. Ethnicity is not the same thing as race or national origin.
National origin is relatively simple. It is the country from which you or your ancestors came. This is complicated by the fact that many people have ancestors from many different countries, but it is a relatively straightforward idea.
Race is a way of classifying people that depends on their visible physical characteristics. These are characteristics like skin color, type of hair, and shape of eyes. We judge a person’s race simply by looking at them.
Ethnicity is related to each of these in some way, but is not the same thing. We can define an ethnic group as a group of people who are distinguished from other people mainly on the basis of cultural characteristics. The members of the ethnic group can define their own group or the group can be defined by outsiders.
Let us look at some examples of this. Many people who are from the Dominican Republic (their national origin) are what we in the US would call “black” or “African American. This is their race. But they tend to be classified as members of the Hispanic ethnic group. The reason for this is that they speak Spanish and have a culture that has been strongly influenced by being colonized by Spain. As another example, there are people from Spain and France (national origin) who do not identify themselves as ethnically Spanish or French. Instead, these people identify themselves as ethnic Basques. They are of France or Spain, but their culture is Basque and so they are part of that ethnic group.
Thus, ethnicity is a matter of culture whereas race is a matter of physical appearance and national origin is based on where you or your ancestors were born.