There are a lot of elephants in a lot of rooms these days. The popularity of an elephant in the room in general English has increased ten-fold since the early 1980s. It is a forceful metaphor for something everyone knows about but no one wants to talk about. It makes a good, eye-catching, title for a commentary or editorial, which is where most of PubMed’s 280 elephants are.

The first, from 1993, is, “The elephant in the waiting room: an alcoholism-awareness tool for medical curricula”. This is an odd title, because surely it’s not the tool that’s the elephant but the failure to acknowledge alcoholism. Two hundred and fifty elephants are from the last 10 years; over 40 from 2016. In all, more than half don’t have abstracts, often because they are letters or comments, so it’s impossible to know if the metaphor is appropriate, especially for the ones whose titles are just, “The elephant in the room”. Perhaps they are about real elephants; some PubMed articles are.

But scanning down the 100 articles that have abstracts doesn’t convince me that this useful metaphor is being used properly. It seems rather often to be used more in the sense of an awkward problem that is difficult to solve. For example, L-DOPA, although the mainstay of treatment in Parkinson’s disease, may cause problems via its metabolites. That is a problem, but no one pretends that L-DOPA is perfect. Another article describes reasons for thinking cerebellar pathways are important in addiction. But that is an example of lateral thinking: of thinking outside the box, to use another metaphor: the cerebellum may be an elephant, but it is in another room and most people can’t see it.

A proper use was in a dental journal, in an opinion piece pointing out that academic dentistry in the UK is thriving, and new products are being advertised, but the profession as a whole is suffering economically. Another appropriate elephant was the waste of resources caused by charities competing for funds during large scale disasters.

Some elephants in the room are really—a much older metaphor—spectres at the feast: a presence spoiling one’s enjoyment. Writing of the overall success of erythropoietic therapy in renal failure, the authors rightly describe the rare problem of pure red cell aplasia as a spectre.

A similar expression is skeleton in the closet, which originally had moral overtones of a guilty secret, but may now mean simply something unpleasant. One of the PubMed articles was about a blocked toilet leading to the discovery of a skeleton in the septic tank.

Neville Goodman is a retired consultant anaesthetist and a writer. He is co-author of a book on medical English.

Competing interests: I have read and understood BMJ policy on declaration of interests and declare that my only competing interest is my co-authorship of a book about medical English.