Nowadays we tend to think of words for diseases as being quite clinical and precise, but before medical science had come that far, names for various illnesses and conditions gained much more colloquial use. In fact, many adjectives we use today had their origins in the names of diseases. I hope you’re feeling healthy as we enter the disease-ridden corridors of the English language…
poxy - an adjective of general insult. The word pox covers a variety of diseases that cause sores or pustules, such as chicken pox and smallpox as well as syphilis. The adjectival form started with the literal sense of having pox, and within 50 years had become a more general insult. Presumably the negative social implications of syphilis added to its insulting connotation, but also the fact that pox can also mean any plague or curse more generally.
mangy - scabby; squalid, shabby. Mange is a skin disease which causes poor condition of the fur. The word may have been applied to humans more commonly in earlier centuries, but now is used only of animals. The use of the adjectival form would seem to be quite obvious, but apparently took over a century to develop in English.
scurvy - contemptible, despicable. The disease scurvy is caused by deficiency of vitamin C, causing a whole host of unpleasant symptoms. Apparently in this case the adjective came first, meaning scabby and generally ill and disgusting, and was adopted as a name for the disease about half a century later. It is no mere coincidence that we tend to hear the word now primarily in Pirate Speak, because scurvy was notoriously a disease of sailors, and a sailor with scurvy was notoriously useless.
rickety - unsteady, likely to collapse. This is the adjectival form of the disease rickets, a vitamin D deficiency that became especially common among children during the Industrial Revolution. Its effect is failure of bones to develop properly, meaning that a rickey person is indeed unsteady. Nowadays it is used only of objects such as furniture, and no longer applied to people. The disease itself is no longer common except in conjunction with areas of general malnutrition, so the disease is much less known than the adjective, and the figurative use is the only one that remains.
measly - contemptibly small. The measles is a disease which causes little spots all over, and perhaps the adjective comes from the size of the spots. On the other hand, it may just come from the general pattern of disease adjectives to become insults indicating little worth. What’s interesting here is that the adjective’s connection to the noun seems to have entirely disappeared as far as common usage goes. How many people complaining of a measly serving of food have any idea of the word’s origins?
jaundiced - affected with bitterness or envy, with a distorted or cynical view. The disease jaundice is caused by an excess of bile in the blood, which gives skin and the whites of eyes a yellowish color. The color yellow as well as the humor “yellow bile” were associated in classical and medieval medicine with anger, aggression, and envy, although the figurative use of the adjective is not recorded until about 1620.
myopic - shortsighted, lacking foresight or insight. The medical condition of myopia is simply near-sightedness. The figurative sense presumably had to wait until the neo-Latin medical coining of the eighteenth century had made its way into common usage. What’s interesting about this one, as opposed to, say, rickety, is that when you call something or someone myopic meaning “narrow-minded” you are very conscious that this is a metaphoric use.
There are a couple of general themes here. The first is how easily suffering from a disease or medical condition makes one an object of contempt. Clearly it is not desirable to have a disease, and having unpleasant symptoms is a bad thing, however it is interesting to note that a “scurvy dog” is not simply an innocent sufferer deprived of necessary vitamin C. To call someone scurvy is to say they are worthless. A second note is that before hospitals and quarantines and modern privacy, people lived cheek by jowl with diseases of all sorts, were all too familiar with their symptoms, and were quite understandably horrified by the victims. Under those conditions it isn’t surprising that people would more readily use words for diseases in colorful figurative ways, and I suspect that we will not be seeing much in the way of new adjectives coming from new medical terms taking on metaphorical meanings. And finally, adjectives are more likely to take on an independent life, no longer tied to their original diseases, when the diseases become less common and/or when the older words for the diseases are replaced with more precise clinical jargon, leaving the older words alone with their colloquial meanings.
[Pictures: Aztec smallpox victims, drawing by anonymous artist, 16th century (Image from Wikimedia Commons);
Rickets, wood engraving by Albert Abramowitz, 1935-43 (Image from The Met).]