Well, its meant to describe people who have a common gene pool which originated in a specific geographic area at a time when isolation was pretty much the norm among human populations. As far as I know that concept is still a good one no matter what names you give to the groups.
Most geneticists cast doubts on the validity that all European people (to say nothing of the semitic peoples that are classified as “caucasian”) came from the caucauses mountains. This is a 19th century idea with few serious supporters.