Whenever I find myself needing to translate 24-hour time (buying a train ticket in Europe, for example, or anytime someone references a time in a movie about the military), it takes me…way too long. It should be simple math – or memorization, really – but nevertheless, it trips me up. I, and I’m sure many Americans, are much more comfortable with 12-hour time, the “a.m.” and “p.m.” demarcations telling us all we need to know. But…do we know it all?
If I asked you what exactly “a.m.” and “p.m.” stand for, would you know?
Like literally anything else, the abbreviations come from Latin. A.M. means ante meridiem, which translates to “before noon/midday.” So, P.M. means post meridiem – after noon.
The abbreviations have been used since the 17th century, if you can believe it, and the 12-hour clock goes back even further, to the ancient Egyptians. They relied on a sundial to tell time, which, as you can imagine, wasn’t possible after sundown (they’d switch to a water clock at night). But the point remains that their time-telling ability was reliant on the 12-hour timetable.
It also became cheaper to use a 12-hour clock than 24-hour models, and we know money makes the world go round – literally. And as far as the number 12, well, the ancients loved it, hence why we have 12 months, 12 zodiac signs, etc. We humans are simply creatures of habit, and so it stuck.
Next time you want to impress-slash-annoy someone, pull out something like, “Will the event be starting ante meridiem, or post?”
Do you ever prefer to use 24-hour time?