If you’re on tenterhooks, it means you’re in a state of anxious anticipation or suspense. But what IS a tenterhook? The answer goes back to a 15th-century manufacturing process. Also, you probably have a term for those crumbs that...
A month of Sundays, meaning “a long period,” or “longer than I can actually figure out,” goes at least as far back as the 1759 book The Life and Real Adventures of Hamilton Murray. This is part of a complete episode.