It turns out that the word nostalgia means homesickness. Some of us weren’t in class the day the teacher talked about nostalgia. Some of us thought the word referred to that feeling of pleasure, tinged with gentle melancholy, that can arise when you think of something that had been familiar and meaningful to you in the past.

As it happens, we were wrong. All of us around here were wrong. The word was composed in the 17th century to describe a malady, severe homesickness, which was first noticed in Swiss mercenaries. Those Swiss mercenaries were sent all over Europe and, no surprise, they got homesick, extremely homesick. The word incorporates two Greek words, (nóstos), meaning a return home, and (álgos), meaning pain or ache. When it comes to making new words, the obscurantist medical profession gets out the Greek and Latin dictionaries.

I looked up nostalgia in Webster’s Collegiate Dictionary, Fifth Edition. (That’s a classic edition.) Yup, there it was. The total definition is one solitary word: homesickness. That edition was based on the famous Second Edition of Webster’s New International Dictionary which was copyrighted in 1934, so we turned to a more up-to-date volume, Webster’s Ninth New Collegiate Dictionary, which was copyrighted in 1989. The number one definition was still homesickness.

But there was also definition number 2: “a wistful or excessively sentimental sometimes abnormal yearning for return to or of some past period or irrecoverable condition.” Have you got that? OK, we’ve already admitted not being in class the day our teacher discussed nostalgia, but I’m sure none of my teachers would have described nostalgia as an abnormal yearning.

The most recent edition of the New Collegiate Dictionary is, I think, the eleventh and I don’t have it at hand. But Merriam-Webster’s current online dictionary has a 148-word history and etymology of  the word nostalgia that will knock your head off. I mean, it’s ultra-complete. And if you’re curious enough to wonder about such things Merriam-Webster says that word nostalgia was coined by the physician Johannes Hofer (1669-1752), a native of Mühlhausen/Mulhouse in Alsace, in his doctoral thesis Dissertatio medica de ΝΟΣΤΑΛΓΙΑ in1688.

I don’t know if looking at some old tie-dyed T-shirts or an old snapshot of you and a certain youthful somebody would give you a wistful or excessively sentimental or maybe abnormal yearning to return to some past period or irrecoverable condition. On the other hand, if you’re in Rome and visit Vatican City and you see one of the Pope’s Swiss guards looking rather sickish, you can say, “Ah, nostalgia!”