The uncanny valley of mutated cognates
So an Irish Independent article described a generation as "Mid-century enfant terribles". I immediately threw up in my mouth a little bit, and was unable to read any further. Part of me wants to go back & check the author's name so that I have a target for my rage, but I won't. I won't tolerate that smell for a detail of such secondary importance - that would be like double-checking a loose stool for sweetcorn.
There's 3 options that might be considered for pluralising enfant terrible.
- 1) Enfant terribles
- 2) Enfants terrible
- 3) Enfants terribles
Option 1 is to completely ignore the syntactic elements of the imported phrase. 'We use it in English as a noun, so we'll pluralise it as if it were an English noun'. The trouble is that this would take some willful ignorance. Even with little or no knowledge of French, if your writing is sophisticated enough to include a phrase like enfant terrible, then I'd expect you to see that Enfant is the noun in this phrase, and terrible is the adjective. With a different phrase that's a little more obscure - say Bête noir, you could legitimately plead ignorance and tack an 's' onto the end - since neither Bête nor noir is instantly recogniseable as the cognate of an English word. Bête noirs is probably not strictly correct, but it doesn't turn me off my lunch.
Option 2 is a fair attempt. It follows a familiar pattern used when pluralising English compound phrases: "Pluralise the noun and not the adjective/preposition that completes the rest of the phrase".
Application of this pattern in English is usually totally unremarkable, such as in phrases like Pieces of cake or Doctors of philosophy ("piece of cakes" sounds childish and is obviously wrong).
It's a little less straightforward (though still 'correct') in phrases that have a weird word-order - (directors general or sergeants major) - or in compound words like mothers-in-law or passers-by.
Applying this pattern to a French phrase doesn't seem consistent though - we've broken down the borrowed phrase into its syntactic components, but if we're acknowledging that enfant terrible is a French phrase, then we should expect its plural to be a French phrase too. This leads us to Option 3
Option 3 is the correct plural in French for the phrase. In French, adjectives change their endings to reflect the gender and case of the noun they describe. We're really not used to this in English at all, so it can seem a little jarring. Usually that's ok, because the pluralised French phrase is just as unfamiliar as the singular French phrase. Enfants terribles looks especially unnatural, because we recognise the word terribles as a weirdly mutated adjective.
Noms de plume, and soupes du jour are much more palatable, because these French-language plurals follow exactly the same rule in French as they would in English.
Chaises longues follows the 'correct' rule, and it doesn't look too awkward - because even though longue is a recogniseable cognate of English long - it's just far enough away that tacking an 's' on doesn't make us squirm the way that terribles does.
Marbh le tae is marbh gan é
This gaelic phrase means "Dead with tea and dead without it" - damned if you do and damned if you don't.
If you try to pluralise Enfant terrible, you can choose between being incorrect and awkward, or being correct and awkward. If you want your writing to be easily readable for most of your readers, it's probably a good idea not to use pluralised borrowed phrases at all. That way, you can steer safely clear of the many possible faux pas.