Caucasian people are actually the people from the Caucus mountains. Using the ethnic term "Caucasian " to refer to light skinned people is from a very racist and outdated Victorian theory that was invented to explain how people emigrated through Asia and Europe and was used to "prove" (falsely of course) that light skinned people are superior to dark skinned. Actual Caucasians have been asking that people stop using that term to refer to "white" people in general. Between the fact that it is inaccurate, the problematic history behind it, and that they have asked and it is their word for their people, we should respect that and stop using it unless actually referring to a person of that specific ethnic identity.