What Do AM and PM Stand For?

What Do AM and PM Stand For?

Updated: November 13, 2020

These periods AM and PM, are as old as a standard time measurement, but some don't know their meaning. They came into play in the 16th century and have since been the basis of time telling. Each of the periods runs for 12 hours and is prevalent among English speaking countries.

What Does AM Mean?

The term 'AM' is an abbreviation of the Latin phrase Ante Meridiem. It means 'before midday' and is best used on a 12-hour clock. Hence, once you see AM attached to a time quote, you should know it says before noon.

However, it's a bit confusing when using a 24-hour clock. Bottom line? AM tells you it's still morning hours.

What Does PM Mean?

PM is the acronym for the Latin phrase Post Meridiem. It signifies that the day has gone past midday. It starts at noon till the early hour of the morning. Thus, immediately after 11.59 AM, the next is 12 PM signaling the start of the second phase of the day. This also applies to 12-hour clocks.

Noon and Midnight: AM or PM?

The terms are used for the 12-hour clock. But it becomes a bit confusing when describing noon and midnight. Most persons think noon should be 12 AM because it's day and midnight, PM since it's dark.

However, the fact is that noon signifies the start of the second phase of the day or evening. Hence, as the first hour of the evening, it should have the PM attached to it. Likewise, midnight is the start of a new day or morning. So it has AM attached to it even though it's still dark.

What time is noon?

Noontime is usually the middle of the day or midday. According to conventional timing, noontime is by 12 every day. It also shows the start of the evening or that morning has ended.

Is noon AM or PM?

This is one of the biggest confusions in the 12-hour timing standard. But from the conventional timing standards, any time after 11.59 has entered the next cycle. Therefore, noon refers to 12 PM since it has begun the best phase of the day.

What time is midnight?

Midnight, as the name goes, is the midpoint between night and day. It signals the start of a new day. Hence it is regarded as an early hour of the morning. Conventional time refers to 12 (after 11.59 PM) as midnight.

Is midnight AM or PM?

Just like noon starts by 12 PM in the afternoon, midnight is the start of a new day. The day begins at 12 AM while it's still dark. So, midnight is 12 AM.