Some countries, like the US and Canada, use the 12-hour Time System, dividing our 24-hour day into two equal parts.
This comes with a catch; each hour happens twice. Most reading this won’t be a stranger to this idea. 6 am is the morning version of the 6’s, while 6 pm is the evening. It’s a simple fact of life many of us never stop to question, but here’s one: what exactly do am and pm mean?
For starters, it’s important to note that am and pm are actually a.m. and p.m. Most of us just don’t get into the habit of including the periods for convenience’s sake. These time of day indicators are actually abbreviations of Latin phrases. A.m. stands for ante merīdiem, meaning before mid-day. P.m. stands for post merīdiem, meaning after mid-day.
Which, technically speaking, should make 12-noon 12 m, since the m stands for merīdiem/mid-day, after all.