"Caucasian"

I've found myself so many times trying to explain why Caucasian is not a synonym for white, nor is it the polite way to say "white," as if that needed a euphemism. If you trace back a "real" Caucasian, as defined by scientists who failed to find a biological basis for determining race and then tried to define race by origin, you would actually only get a very small handful of people in this world tied to a very specific geographical region. I think this sums it up quite well:

The dominant use of the word ‘Caucasian’ instead of ‘white’ effectively hides
color behind a wall of pseudo-science. Despite a history of scientific
falsification, ‘Caucasian’ was adopted into American vernacular in the
mid-twentieth century as a means of reconsolidating whiteness as a biologically
distinct category of people (Jacobson 1998). (Reitman, 2006, p. 272)

In truth, the act of using ‘white’ only reveals to whites their own
privilege, the historical politics of whiteness. (Reitman, 2006, p. 273)

In other words, using the term "white," instead of the scientifically inaccurate "Caucasian," strips away this notion that "white" is normal or default or neutral and that people of color are inherently deviants of this construction of normalcy.