What’s the difference between a psychiatrist and a psychologist? I remember wondering this years ago, and learning that a psychiatrist is the actual medical practitioner, while a psychologist is an academic who studies the human psyche.
I had this distinction memorised for many years without knowing the etymologies of the words. (Well, without knowing the etymology of ‘psychiatrist’ – ‘psychology’ is a fairly easy etymology to work out.) But recently I wondered where this ‘-iatrist’ ending comes from.
‘Psychiatrist’ is obviously just the agent noun from ‘psychiatry’, which is in turn from Greek psykhe, meaning ‘mind’, and Greek iatreia, meaning ‘healing’. So it’s a perfectly-formed word – no etymological quirks.
There are a few other Modern English words that use this ‘-iatry’ ending – or its derivatives and variants ‘-iatric’ and ‘-iatrist’. I’ve listed some of these in the table below. Curiously, in each case, only one form – the adjective, the noun, or the agent noun – is commonly used in Modern English, with the others not, and sounding a bit out-of-place. I’ve put the common-ish words in bold.
| Adjective | Meaning | Noun | Agent Noun |
| bariatric | ‘of or pertaining to obesity’, ‘of or pertaining to the healing of obesity’ | bariatry | bariatrist |
| geriatric | ‘of or pertaining to old age’, ‘of or pertaining to the care of the elderly’ | geriatry | geriatrist |
| paediatric | ‘of or pertaining to the care of children’ | paediatry | paediatrist* |
| podiatric | ‘of or pertaining to the healing of the feet’ | podiatry | podiatrist |
(*Of course we usually use the word ‘paediatrician’ here, but there’s no reason why it couldn’t be ‘paediatrist’.)
Not a very large selection of words. It’s curious that such a useful word-forming element is not used that much.
As I have done with the other posts in this series, however, we can get creative and imagine some new words that use this ending.
| Noun | Meaning | Adjective | Agent Noun |
| ailuriatry | ‘the healing of cats’ | ailuriatric | ailuriatrist |
| cyniatry | ‘the healing of dogs’ | cyniatric | cyniatrist |
| chiriatry | ‘the healing of the hands’ | chiriatric | chiriatrist |
And more. Such words could be quite useful in fantasy fiction, where there might be various different kinds of healer.