“Laura is suffering from a medical condition called pleurosis, which made one of her legs shorter than the other.”

In Tennessee Williams’ The Glass Menagerie, Laura remembers a handsome and popular boy from high school who had “always” called her “Blue Roses” because she had missed some school while suffering from pleurosis and he had mis-heard the term. That’s a mistake that aficionados of error would call a Mondegreen, but in the play it’s a cherished, and perhaps exaggerated, memory.

Laura is also painfully self-conscious because in her youth she had had to wear a leg brace and, with the pitiful vanity of most of us who worry about some perceived flaw, believed every eye was on her clumsy self whenever she walked into a room. She no longer needs the brace, but whatever the affliction was, it has shortened the affected leg. Williams directs that the actress playing Laura suggest a limp rather than actually play it (although I saw a production where the director defied Williams on this, to the play’s detriment). The young man, now grown up and entering the play as the Gentleman Caller, protests that he never even noticed Laura’s brace in high school; the audience is left to decide whether this was because it really wasn’t as awful as Laura had thought, or because he had never really noticed much about her.

My student is describing Laura. She is also writing new chapters into the annals of medicine.

All teachers of writing at the college level have struggled to explain to their students the difference between “defining your terms” and “telling the reader what the dictionary says.” Young writers seem determined to share Webster’s wisdom with their readers—who, they evidently think, have limited vocabularies and no dictionaries at hand. The words they choose to define are quite often perfectly common words, and the definitions are, typically, straight out of some print or online dictionary, with no added nuance or emphasis. Sure, once in a while including the dictionary definition can be useful to a paper: I remember writing a paper on The Rainbow that used the multiple definitions of “rainbow” in (probably) Webster’s Second as the organizing principle of the discussion, and the professor and I seemed to think that worked pretty well. But USUALLY, I intone to my classes, we “define our terms” when we are modifying, adding to, qualifying, making figurative, or otherwise appropriating a term to our own purposes.

Obviously this student wanted to define her terms—or Williams’ terms. I don’t think it was my preaching that kept her away from the dictionary for that purpose; I think she just thought Williams had given Laura one affliction instead of two (three, if to the leg problem and pleurosis you add neurosis, that shyness of hers). Laura had pleurosis; Laura limps: pleurosis causes shortening of the limbs, Q.E.D.

Perhaps she did go to a dictionary and failed to find “pleurosis.” It’s not a term much in use.

But she would have found, right where she had looked for “pleurosis,” pleura, “the delicate serous membrane that lines each half of the thorax of mammals and is folded back over the surface of the lung of the same side”; pleurisy, “inflammation of the pleura usually with fever, painful and difficult respiration, cough, and exudation into the pleural cavity”; and, a little farther down, pleuropneumonia, “combined inflammation of the pleura and lungs.” (Thanks as usual, Mr. W.) Today, if she were to Google “pleurosis,” she would be helpfully directed to numerous sites offering definitions of “pleurisy,” which is probably what Laura had suffered from for a while one year in high school.

Armed with that information, my student might have wondered for a least a moment how a lung (or pleural) disease could shorten a leg—a part of the body not mentioned or even hinted at in any of the above definitions. Oh, please, please, then, DON’T let her have looked the word up! I would far rather contemplate a student too self-confident or too lazy to consult a dictionary, than a student who blithely assumes a causal connection between afflictions of two different systems and two different parts of the body.

Next time I launch into an explanation of “defining your terms,” I’d better include a brief comment about “engaging your brain.”