Sometimes, halfway through the forest path of a sentence, where did it go? There was a flow of syntax that – something ate it. But what? An anaconda? A python? Worse: it is that most uncouth lexical reptile – the anacoluthon. It slips into a syntactic constituent and devours the tail of it, and in its place leaves the tail of another constituent to be grafted on.
But what a word, a snake in its own right, eleven letters, crawling into the modern era little changed from ancient times, like a coelecanth in the net of your page. Yet it is not such an ugly fish as that; indeed, it has a soft, liquid sound with just a single hard stop. It would do well as a word from a Celtic language – or, more to the point, an invented language from fantasy fiction. It would fit right into Tolkien’s Sindarin: “Fanuilos, le linnathon, nef aear, anacoluthon” – though it would break the rhythm of that poem, since the stress is on the /u/, as in Lúthien.
In fact, it comes from Greek: ἀν an ‘not, without’ and ἀκόλουθος akolouthos ‘following’ (do you notice how yet again we’ve shifted the stress from its placement in the Greek, which would be more natural to us?). The word is for something that does not follow what came before. To use the Latin equivalent, it is a syntactic non sequitur. You all know people who speak like this: the sentence flow they started, it’s changed halfway through – bang, you know? It can be used for topic fronting: “That cake you gave me, the dog ate it”; it can be used for rhetorical or poetical effect: “If only I could have – how could that have been?”; it can be used just because the train of thought went through a tunnel and when it came out everyone had changed cabins: “I brought that fruitcake that she made it with the raisins and the rum is so tasty.”
It is sneaky and slippery, this anacoluthon. The one thing you can be sure of is that it retains the element of surprise. You do not see it coming. And if you look behind you, you will not see it there either. Yes, it is invisible. But you did not see it behind you because it was not there in the first place – it does not follow.