I have been rereading a lot of P.G.Wodehouse lately, particularly enjoying Jeeves and Bertie, and he uses the word 'blench' a lot. I always assumed this was a variation on 'blanch' - ie to go white. It seemed to fit, someone would get a shock or bad news and would 'blench visibly'. But apparently it means 'to shy away, quail'. That is, quailing of the shying away kind, not the bird kind.
I also learned, no matter how many times you check something, CHECK IT AGAIN! I had 15 copies of a book I had edited delivered to me today, to distribute to authors etc, and found that I had in the end sent the printer the wrong version. I had sent the 'final' version for a different purpose, not the 'final' version for the printer. So I spent a few Saturday hours fixing that mistake.
But maybe I learned something today.