In an earlier episode, Dennis from New Smyrna Beach, Florida, was having trouble recalling a word that denotes the interval between the end of an event or of someone’s life and the death of the last person that has a meaningful memory of it. We had a couple of suggestions, but they weren’t what he was searching for. Fortunately, a listener in Geneva, Switzerland, wrote in with the likely answer: saeculum. The ancient Etruscans and Romans would make a sacrifice to the gods on behalf of everyone alive at the time of a significant event, and when all of those people had died, the gods supposedly sent a sign that a new sacrifice was needed. That period was called a saeculum. The Latin word was adopted whole into English to mean “a long period of time.” The genitive form, saecularis, meaning “of an age,” also gave us secular, referring to worldly matters of a particular period. Secular can also refer to something that exists or occurs through several ages. For example, economists use the term secular inflation to refer to inflation that takes place over a long period of time. Similarly, in his poem “The Garden,” Ralph Waldo Emerson refers to a slow-ripening, secular tree. This is part of a complete episode.