It’s common to almost everyone that they figure out what they see, coming up with an explanation that seems reasonable, at least given what they know at the time. Before things like germs, viruses, and some of the actual processes operating in your body were discovered, people dreamed up any number of explanations for why someone might feel this way or that, suffer from an illness, or generally have whatever symptoms they might experience.
One set of ideas about the way bodies functioned was the “humors” theory. This was pretty well accepted during the Middle Ages in Europe. It suggested that your body contained four substances called “humors,” and they were supposed to be in some sort of balance. Practically any sort of illness or disease might be the result of an imbalance. The four humors were black bile, blood, phlegm, and yellow bile. Yellow bile was also called “choler,” which sounds vaguely familiar to us today because although it turned out not to be even remotely true that anything like “humors” exist, they did have a lasting effect on the language. One of the effects is that we still talk about “cholera.” You might even be described as “choleric” when you’re feeling irritable or in a bad mood.
The other humors also gave us some words we still use. When you’re optimistic, you’re “sanguine” — that’s from the French word for blood, “sang.” When you’re calm and unemotional, you’re “phlegmatic,” which you’ll notice is based on the word “phlegm.” And when you’re “melancholy,” you’re sad and downcast, which in the days of the theory of humors meant that you had an excess of black bile. “Melancholy” comes from the Greek words for black (melas) and bile (kohle).
There’s another word for “melancholy” that’s also based on the idea of humors: “atrabilious.” While “melancholy” has its roots in Greek, “atrabilious” comes from Latin. It’s nearly a direct borrowing of “atra” (black) and “bills” (bile).
But wait, you say, isn’t the Latin word for black “niger?” It is — “atra” is another Latin word for black. It hasn’t made its way into English quite as successfully as “niger,” but there are a few English words based on it. One, of course, is “atrabilious,” but you’re unlikely to run into that particular example very often unless you read etymological trivia (oh, which you’re doing right now…) But you’re probably familiar with “atrocious”, which is based on the figurative use of “atra” as in “black of heart”.
There’s also a bit of a surprise in the next “atra” word: “atrium.”. We think of an atrium as a large, sunny, expansive lobby in, say, an urban hotel, not anything that we’d call “black.” But the word comes from Rome, which also had large open halls. And in Rome, since they lacked both plate glass and electricity, the halls were lit with fire. The smoke from the fire stained the walls black to the extent that big Roman halls were called “black halls,” or “atria.”
It’s counterintuitive today, of course, but then there was a great deal back then that doesn’t seem all that sensible to us now. After all, the idea of humors gave rise to the nutty idea that if there was something wrong with you, the best course of action might be for the “doctor” to make you bleed. Now there’s an idea that’s really… atrocious.
