{ like a barefootsong }

I was a reading a book today, in Spanish, and I came across the phrase "sangre azul" (literally "blue blood"). So then I wondered about the English phrase and how it came to mean people of the aristocracy. Technically everyone's blood is blue when it's inside them; it only turns red when exposed to the air, hence why your veins are blue not red. So of course I pulled up the good old Oxford English Dictionary as soon as I was back at a computer:

blue blood: that which flows in the veins of old and aristocratic families, a transl. of the Spanish sangre azul attributed to some of the oldest and proudest families of Castile, who claimed never to have been contaminated by Moorish, Jewish, or other foreign admixture; the expression probably originated in the blueness of the veins of people of fair complexion as compared with those of dark skin; also, a person with blue blood; an aristocrat. [cite]

I never thought it was actually from Spanish originally, let alone that it had a racial meaning. Of course it does make sense, since the blue veins aren't as visible in darker skin.

Oh! I bet this also explains the Spanish term for Prince Charming, Príncipe Azul (literally "blue prince"). Since "blue blood" is originally from Spanish, that must be why a "blue prince" is the ideal. I always wondered about that.

Another fascinating lesson from the OED! (Easily "one" of my most favorite books!)