Okay, so I assumed that Radiohead’s new album title was nonsensical.
Then several months later, I read an article in Pulp Magazine using the phrase “Kid A” as shorthand for disaffected Japanese children who turned violent.
Now this is completely in keeping with Radiohead, but I’ve never heard the phrase before.
I had been wondering whether it was a play on “G’day”, the traditional Australian greeting. But as I have no real reason for believing this to be the true answer, you may safely ignore it.