"It's like lambent - everyone uses it, no one knows what it means."
A Suitable Boy, Vikram Seth
Like most writers, I got most of my vocabulary from novels. This meant that as a child, I would refer proudly to appen-dickes instead of appendices and that even now my fella and I will have moments of confusion over how to pronouce something.
It also means that I think I know a lot more words than I actually do.
A few months ago, I was doing a crossword with a friend.
"Transparent - five letters, starts with l?"
We sat thoughtfully for a while, then I said,
"Does limpid mean transparent?"
"I thought limpid meant ... limp," said my friend.
"But you get limpid pools, don't you?"
We looked it up and discovered that it did, indeed, mean transparent.
Another friend works for the Civil Service, and was always being asked to find, "Some factoids we can drop into the Minister's speech." Being a Classics scholar she had her suspicions about this, so looked it up. Sure enough, a factoid is 'Something which sounds like a fact while actually being false.' She then spent several months giggling every time she was asked to provide factoids.
Writers are people who know the names of things. As a child, I used to drop long words into stories simply because they sounded nice (I wasn't alone in this - T S Eliot was a firm believer in occasionally using a word which sounds nice above one which actually means what he says it means.)
As an adult, I'm discovering retrospectively what all these words mean, and I'm having a great time. 'Torrid', for example, I always thought meant passionate, as in 'a torrid love affair'. Actually, it means hot. 'Scintillating' I thought meant interesting, as in 'a scintillating discussion'. Actually, it means sparkling.
It's not so much expanding my vocabulary as focusing it. Now all I need is the courage to actually use some of these words in a sentence without getting them wrong ... who knew the ch in chthonic was silent?