I think of race as an ideology- different groups seem to have roughly similar views about it when they have shared history- it's a social construct, so it's difficult/impossible to really convey to other people what it means to someone. For example, the concepts of white/black races seem to have originated in the US somewhere around 1700 [1], and are noticeably absent from older writings.

For some people, skin color is as meaningless as eye color, but for others everything is viewed through the lens of race, so it has the added difficulty that its meaning is context dependent. The racial jargon is often so amorphous, it's impossible to interpret literally.

1. https://www.amazon.com/Birth-White-Nation-Invention-Relevanc...