The most popular sport in the wizarding world, it’s played on broomsticks, and involves each team… I jest, of course. Quiddity is a philosophical concept that describes the thing that makes something what it is – its essence. So you could write: ‘Emma’s weekly posts capture the quiddity of complicated words in straightfoward prose.’ Oh really? How kind of you to say, thank you so much.
It’s nothing to do with HP. But there are no good pictures for ‘essence’.
Now, my two major word-of-the-week sources (which are Wikipedia and Merriam-Webster), disagree on the meaning of quiddity. The one above is Merriam-Webster’s definition, which is the one I’m going with because it’s easiest to understand. But according to Wikipedia, quiddity is a bit more complicated, and describes the properties that a particular thing shares with others of its kind. This makes it the opposite of something called ‘haecceity’ or ‘thisness’ (which apparently is an actual word) i.e. a positive characteristic of an individual that causes it to be this individual, and no other. See why I’m going with the first one?
Quiddity comes from a Latin word, ‘quidditas’. That’s a translation of a Greek phrase ‘to ti en einai’ , meaning ‘the what it was to be’, which sounds like something a drunk person would say.
Quiddity can also refer to a small and usually trivial criticism or complaint, or to a quirk or eccentricity in someone's behaviour or personality. Hamlet uses it in this way in, well, ‘Hamlet’ in his graveside speech, referring to a lawyer: ‘Where be his quiddities now, his quillets, his cases, his tenures.’
That’s not a very fun note to end on, so here’s a quidditch joke:
Why should you never have sex with a wizard?
Because you might catch Hogwarts, and they never stop quidditching.
(I didn’t say it was a good joke.)