First impressions: This word brings to mind Falstaff, toadstool, fad, fall, tool, folds, failed, field, fault, perhaps old fool. It seems to have a floppy, soft feeling from the /f/ and /l/ and it carries at its end a taste of every word that ends in ool, including fool, stool, snool, drool, cool, chacmool, pool, and of course tool (not so much wool).
Visual: It has the oo eyes looking out at you, and it has no shortage of ascenders – four out of eight letters lift their arms. It’s a modestly unwieldy-looking word. It doesn’t look like something you could easily collapse and carry away.
In the mouth: The front of the mouth seems most used, but there are three cases where both front and back are involved: in the vowel /u/, the tongue is up at the back but the lips are also rounded; and in the two consonants /l/, at the ends of their respective syllables, the tongue is up at back as well as touching at the tip (in some versions of English it doesn’t touch). So for about half the time the articulatory area has a sort of U shape to it.
Etymology: This word has traced a vaguely U-shaped etymological path. It comes originally from Old High German faldstuol, from faldan ‘fold’ and stuol ‘stool, chair’; that was borrowed into medieval Latin as faldistolium, and from there it came back into Germanic – in this case English – as faldstool. It also made its way into French, where it ultimately became fauteuil ‘armchair’ (I find fauteuil a much more impressive-seeming word than suits such a homely meaning).
Semantics: A faldstool was originally a folding chair, but not necessarily just any folding chair. It has become a term for a chair that a bishop (or the Pope) sits on when visiting locales away from his cathedral (a cathedral is where you find the bishop’s chair – cathedra means ‘chair’), or a portable altar made the same way. What way? It looks like a U sitting mirrored on a sheet of glass – or like an X made from U’s. Some faldstools don’t look especially foldable, but that was the origin of the design, anyway. (Do a Google image search on faldstool to see what I mean.) It looks very much like a curule chair, for those few who have any idea what that is – indeed, sometimes this term and that one name the same object.
Where to find it: Under a bishop’s butt, or anyway on a dais and ready to receive the episcopal posterior. But only when the bishop is on the road. Also sometimes with a bishop kneeling in front of it. That bishop may be the Pope.
OK, well, that’s where to find its object, anyway. Where to find the word? In writings about Catholic or Anglican liturgy, especially high ceremonial. My mother, who suggested this word, saw it in an article about the ordination of a Catholic priest – presumably done by a bishop who had a faldstool for the occasion.
I don’t know about you, but I find this word feels curiously undignified for what it means and where it’s used. A stool now is a very homey thing generally, and at least for my tastes the fald does nothing to add dignity. Oh well – language is arbitrary; it’s not the word’s fault. And if you happen to love in-group arcana such as the words for liturgical ceremonial appurtenances, from narthex to baldachin including every alb, cope, ciborium, mitre, crosier, and whatever else you can spot, well, here’s another one – and a very Germanic-looking one indeed, in spite of its Latin detour.