Ahah! I said, no doubt a cheap artificial fabric that lived a short and unlamented life in the middle of that decade. But no one had heard of it, Even the Internet only had references to the series itself. So it is probably a nonce-word, created by the writers in order to avoid using the commercial name of a real cloth. I'm not sure why they would need to do that, but they certainly seemed to have done it.
This, naturally, led me to idly think about rare words (and split infinitives). There are several ways of defining rareness of words. There is the Googlewhack which, if I have understood it correctly, is an expression contrived in such as a way as to produce exactly one result on Google. They are usually combinations of otherwise unexceptional words, and so could be considered nonce-terms, rather than nonce-words. It's a kind of game, I suppose, for those who are bored with Mornington Crescent.
A nonce-word is a word that is created for the nonce, a word which did not previously exist but whose meaning is made transparent by the context. They can be very effective in the right hands, and they usually need a particular aesthetic to make them work. They must feel right, as well as working semantically. Such words are rarely picked up by anyone to be used again, and so remain as unique examples in the written (or spoken) language.
Then there is the hapax legomenon, which classically educated readers will recognise as meaning spoken once. This refers to a particular text or body of language, so it is possible to say that '...' is a hapax in the King James Bible, or that 'Honorificabilitudinitatibus' is a hapax in Shakespeare. There are also hapaxes in the whole of a corpus of language used for linguistic research, which these days are very large, or in English literature generally.
Here the OED comes in, since it covers just about everything ever written since English was identifiable as such. They use a superscript -1 to indicate a word which has only been found once in the surviving corpus of the language. It doesn't apply to unique variations on other words, of which there are many, but to words which appear to have no brethren of any kind. Sometimes a meaning can be inferred from the context in which they are found, sometimes not.
The OED also has a superscript -0, for a word of which no instance at all is found in the language. This rather esoteric category could, in theory, either be empty, or arbitrarily large, depending on how you interpret it, but in fact it refers to words which have only been found in dictionaries or other kinds of word list, and never actually used in text.
Spanish has a word, jitanjáfora, which means a fanciful neologism of euphonious phonology or prosody, with a meaning that may or may not be transparent. They may be nonce-words, hapaxlegomena or complete phrases, and like other such terms, they may be picked up and more widely popularized.
The Owl and the Pussycat contains a famous neologism, runcible, applied to a spoon, which is more nonsense word than nonce-word, as its meaning is not transparent and is almost certainly not intended to be. Oddly enough, the word became so popular that it was given a meaning a posteriori, because it seemed to need one, though it was surely not what Lear had in mind.
Guy Clark's song Bunkhouse Blues contains the line 'At the Broken Heart Ranch you can always get work as a cowfool'. The word appears to be his, a nonce-word used to suggest someone who looks after cattle as a way of hiding from the world. In the song it works.
Talking of good Southern music, Jenny Lewis, in Acid Tongue, refers to being '...in the depths of the godsick blues'. This appears to mean 'sick to god', although I suppose it could mean 'sick of God', in some way. There is also a surname Godsick, which I was surprised to discover, but I don't suppose it's relevant here.
This has been a series of random thoughts on rare words, for no particular reason, which is often the best reason there is.