In the first papers in this series, it was shown that eponyms were often bestowed on physicians and surgeons who were already famous, had made many discoveries never honoured with eponyms, and were often the leading doctors of their day. Only occasionally was the eponym suggested by a friend or colleague; more usually it was a doctor abroad who wanted to show respect to a great man but the choice of the particular syndrome or discovery was a random one. Eponyms may have had their uses. They were usually much shorter than a detailed description of a medical syndrome or anatomical feature and may sometimes have been used as euphemisms in much the same way as, until recently, bedside teachers protected the patients by speaking of ‘mitotic lesions’ or ‘neoplasms’, ‘Hansen’s Disease’ or ‘acid-fast bacilli’. The conferring and use of eponyms appears to be lessening but, as shown in this final paper, they are still used and possibly useful, and can tell us things of interest about the recipient and the proposer.