I like watching the kind of extreme skiing videos where a pair or trio of skilled extraverts in Gore-Tex scale exceptionally steep peaks and then, at the top, on the knife-edge of a ridge, don skis and revert: they slide scenically all the way back down, accelerating, linking turns, cavorting.
I could not do this. I would not scale such a vertical. I would not stand at its vertiginous apex. If I were, somehow, inadvertently, to find myself at the vertex, unable to divert, vertigo would overtake me. My eyes would pop wide open, from e to o; my world would become a vortex, and I would be whorled down the vortical, every turn for the worse…
Vortex and vertex: two words so similar, and yet. Like horse and hearse, perhaps, or person and parson.
In fact, quite like the latter. Because, you see, like person and parson, vertex and vortex started as two versions of the same word. But unlike person and parson, these two -texes didn’t split apart in English. Rather, vortex is archaic Latin for vertex, which is Latin for ‘summit, highest point, top, whirlwind, whirlpool’.
How does one word mean both ‘summit, apex, rocky peak of land’ and ‘eddy, whirlpool, spinning hole in the sea’? I turn to my Latin dictionary and there I find the source: verto, ‘I turn’. A whirlwind or whirlpool turns, of course. But also, a line turns at a corner, and the ground turns at a peak – it stops going up and starts going back down.
We have many vert- words in English, all having something to do with turning, in one way or another. An extravert (now often rendered extrovert by analogy with introvert) is someone who is turned outward. The vertical is that which is turned perpendicular to the horizon. Something that’s vertiginous induces vertigo, which is a sensation of the world turning around you. And so on. And many of these words came up the natural route of daily use via French into English: convert, divert, version…
But vertex and vortex came the other way: someone in English or French wanted a proper term for a thing, and so they turned to the Latin lexicon. Geometers in the 1500s wanted a learnèd term for the peak of a cone or the corner of a polygon, and of course vertex is what such things were called in Latin. But cosmologists in the 1600s, such as Descartes, wanted a term to name the whirling of matter around a central axis, a thing they observed in the stars (Newton’s Principia propounding gravity was still a few decades in the future), and this archaic Latin word vortex served the turn – and then, over time, was converted into a word for such eddies as we see in the sea and sky around us.
And now, somehow, pretty much everyone knows vortex, and it shows up in occasional daily use even among non-nerds, but only mathematicians and similar sorts speak of vertices.
Which, oh, by the way: the plural. Your math teacher will always have said vertices. English being as it is, vertexes is an established alternative, but, English speakers being as they are, it is looked down on. And the plural of vortex? The same obtains. In truth, I’ve long thought that vortexes is common enough, but a Google Ngram tells me that vortices is much the preferred version.
But, as you will see if you look at the ngram, while vertices appear in the plural nearly as often as a singular vertex, most of the time there is only one vortex. If you have cause to speak of vortices, it may be a very bad day, and one you might not slide out of too easily.
Sesquiotica 