I remember when I was a kid puzzling over the "merry little quadroon, who could not be taken in elsewhere, but who was welcome to the `Bhaer-garten'," quadroon being a word I hadn't seen anywhere else, and trying to figure out which boy he was in Little Men. I thought "quadroon" might mean "mischievous child," so for a while I thought he might be Tommy Bangs, but of course he's simply not there, because Alcott couldn't actually take the risk of putting in a mixed-race boy for more than a sentence or two.