Spread The Good Word

It has been many weeks since my last confession, but it’s time for another one: I really like language when used well, and it’s a pet peeve of mine when people bastardize it or just plain get it wrong. The most prominent one in medicine is probably nauseous versus nauseated: if you feel sick to your stomach, you are nauseated; if you’re the resident who has been up for 48 hours sans shower, sans deodorant, and has just returned covered in poo from yet another ED consult for an outbreak of dysentery, then you’re nauseous and make everyone around you nauseated. (For a simple mnemonic, try a quick nauseous/noxious substitution in your head.) But I’m preaching to the choir on this one, n’est pas? What follows, I hope, will be more enlightening.

One particular diction conundrum has piqued my interest since the beginning of medical school: what on earth is the difference between “dilation” and “dilatation”? Is the “-tation” version a made-up word that makes you sound ignorant if used? Or is it akin to the centimeter as “sontimeter” convention which is uniquely medical and as far as I can tell has no reason for its continued persistence other than to make doctors sound more erudite (which can ironically backfire when, as one of my classmates did this year, someone asks you what one is because it sounds so strange). Or could they actually be two different words describing two different things, the nuances of which were obvious to everyone but me? I leaned toward the latter option for a while, but then went more toward the first after asking a couple of surgeons in the family who couldn’t seem to agree or decide between the two. Ultimately, the uncertainty was just too much to bear and I succumbed to my inner geek (we’ll just pretend like that was a struggle) and did a lit search. I figured there had to be an obvious answer, since they are both so commonly used. As it turns out, there’s really not much in the medical literature on this. Maybe I’m the only one surprised by that. Alas, I was not to be deterred. I soldiered on, and am very (overly) proud to say that I have emerged victorious! I think the last time I needed a primary source that wasn’t electronically available was maybe six or seven years ago; at the very least, the miracle of interlibrary loans and PDF scans made it seem like it was all available electronically (a big “Thank You!” to all the librarians out there). But no, as an intrepid etymologist my quest would not be that easy; I was forced to go back to the stacks and sift through bound hard copies of The Journal of Urology, get myself a copy card, and photocopy the darned thing. And now that you’ve earned it by humoring me while I recount my epic odyssey, I will now share with you the Truth (are you as excited as I am? No? That probably speaks well of you):

Bottom line: dilation and dilatation may used interchangeably, though the verb form “to dilatate” is rarely if ever heard. Dilatation appears to be the original word--first seen in Chaucer--from the Latin noun dilitatio (the verb: dilatare); for this reason, the OED sticks with dilatation as the more correct form, but in practice either are acceptable. Credit for all this goes to Bloom, Mory, and Hinman (1); see the citation below for more info and leave a note in the comments if you’re not keen to hunt for the original and I’ll send you the PDF.

So, go forth and spread EITHER of the good words and do so with the conviction of one who can cite a source!

1. Bloom et al. Dilation vs. dilatation: a brief history. J Urol (1992) vol. 147 (6) pp. 1682