# I really despise the "12:00 AM" deadline **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [July 15, 2009, 1:48am UTC](https://boards.straightdope.com/t/i-really-despise-the-12-00-am-deadline/503072 "2009-07-15T01:48:38Z")\ **Posts on this page:** 9\ **Page:** 3
**Author:** ![I\_Love\_Me\_Vol.I](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/i_love_me_vol.i/32/521_2.png) [@I\_Love\_Me\_Vol.I](https://boards.straightdope.com/u/I_Love_Me_Vol.I)\ **Post date:** [July 18, 2009, 7:46am UTC](https://boards.straightdope.com/t/i-really-despise-the-12-00-am-deadline/503072/41 "2009-07-18T07:46:49Z")
> [@](#): > > Originally Posted by \*\* Sophistry and Illusion \*\* > I had a professor in college who delighted in being anal retentive, and instead of 12PM, he insisted on writing 12M, since 12 noon is the meridiem, it’s not post- or ante-meridiem. > > > [@Telcontar](#): > > > > Up until now I did not know what AM and PM stood for. Just never came up. It’s _ante meridian and post meridian_, I believe. Not “meridia **m** ”. Perhaps just a double typo though, I suppose. ---
**Author:** ![I\_Love\_Me\_Vol.I](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/i_love_me_vol.i/32/521_2.png) [@I\_Love\_Me\_Vol.I](https://boards.straightdope.com/u/I_Love_Me_Vol.I)\ **Post date:** [July 18, 2009, 7:49am UTC](https://boards.straightdope.com/t/i-really-despise-the-12-00-am-deadline/503072/42 "2009-07-18T07:49:05Z")
> [@gigi](#): > > I would imagine: Because when it’s light outside, 11:58 is in the morning, and so is 11:59. Therefore, 12:00 is also in the morning. After 12 is the afternoon. Except that 12:00 is neither in the morning or the afternoon. It is just… noon (or 12 noon or 1200). ---
**Author:** ![Ximenean](https://avatars.discourse-cdn.com/v4/letter/x/aca169/32.png) [@Ximenean](https://boards.straightdope.com/u/Ximenean)\ **Post date:** [July 18, 2009, 2:31pm UTC](https://boards.straightdope.com/t/i-really-despise-the-12-00-am-deadline/503072/43 "2009-07-18T14:31:58Z")
> [@I\_Love\_Me\_Vol.I](#): > > It’s _ante meridian and post meridian_, I believe. Not “meridia **m** ”. Nope, it’s _meridiem_. Accusative case. ---
**Author:** ![shantih](https://avatars.discourse-cdn.com/v4/letter/s/f6c823/32.png) [@shantih](https://boards.straightdope.com/u/shantih)\ **Post date:** [July 18, 2009, 5:27pm UTC](https://boards.straightdope.com/t/i-really-despise-the-12-00-am-deadline/503072/44 "2009-07-18T17:27:37Z")
> [@Ximenean](#): > > I understand that in Germany regular people do sometimes say things like “nineteen hours”, although they also use the 12-hour clock in casual speech. It’s a very common usage in Germany, and it throws me off something fierce. I’ll make an appointment over the phone, hang up, and then wonder if the receptionist said 16:00, which I automatically translated to 4 pm, or if she said 6 o’clock. I’ve learned to write it down in my calendar as I’m repeating it in my phone call, and then I don’t arrive 2 hours too early or too late. ---
**Author:** ![I\_Love\_Me\_Vol.I](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/i_love_me_vol.i/32/521_2.png) [@I\_Love\_Me\_Vol.I](https://boards.straightdope.com/u/I_Love_Me_Vol.I)\ **Post date:** [July 18, 2009, 8:17pm UTC](https://boards.straightdope.com/t/i-really-despise-the-12-00-am-deadline/503072/45 "2009-07-18T20:17:52Z")
> [@Ximenean](#): > > Nope, it’s _meridiem_. Accusative case. Thank you. I did not know that. Searching online I see that it is referred to as “meridian” in many places, but I guess they, like me, just always had it wrong. My Latin was never any good anyway! :smack: ---
**Author:** ![Brainiac](https://avatars.discourse-cdn.com/v4/letter/b/8797f3/32.png) [@Brainiac](https://boards.straightdope.com/u/Brainiac)\ **Post date:** [July 18, 2009, 9:26pm UTC](https://boards.straightdope.com/t/i-really-despise-the-12-00-am-deadline/503072/46 "2009-07-18T21:26:10Z")
12am has meant first thing in the morning in question for centuries. Get used to it. It’s no harder than 12:01. If you want a mnemonic, here’s a little poem you can memorize: Twelve A M is like Twelve oh one But one minute earlier The end ---
**Author:** ![Gary\_Robson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gary_robson/32/3448_2.png) [@Gary\_Robson](https://boards.straightdope.com/u/Gary_Robson)\ **Post date:** [July 18, 2009, 10:49pm UTC](https://boards.straightdope.com/t/i-really-despise-the-12-00-am-deadline/503072/47 "2009-07-18T22:49:09Z")
> [@Brainiac](#): > > 12am has meant first thing in the morning in question for centuries. Get used to it. It’s no harder than 12:01. Using a.m. or p.m. with 12:00 has generated confusion for centuries. It’s why we have words for “noon” and “midnight.” They eliminate the ambiguity. ---
**Author:** ![BigT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bigt/32/12044_2.png) [@BigT](https://boards.straightdope.com/u/BigT)\ **Post date:** [July 19, 2009, 6:17pm UTC](https://boards.straightdope.com/t/i-really-despise-the-12-00-am-deadline/503072/48 "2009-07-19T18:17:47Z")
> [@InvisibleWombat](#): > > Using a.m. or p.m. with 12:00 has generated confusion for centuries. It’s why we have words for “noon” and “midnight.” They eliminate the ambiguity. Seeing as the thread was more about the ambiguity over whether midnight starts or ends the day, neither of you really has a point. But 12AM vs. 12PM has been taught in school for so long, that even the most uneducated people in the Ozark Mountains here in Arkansas knows the difference. While I’d love to say that was because the stereotype about us being stupid was horribly wrong, I can’t; it’s just slightly exaggerated. ---
**Author:** ![Richard\_Pearse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/richard_pearse/32/13144_2.png) [@Richard\_Pearse](https://boards.straightdope.com/u/Richard_Pearse)\ **Post date:** [July 19, 2009, 11:37pm UTC](https://boards.straightdope.com/t/i-really-despise-the-12-00-am-deadline/503072/49 "2009-07-19T23:37:02Z")
> [@jjimm](#): > > Is there any notation that actually uses 24:00? Here in semi-24-hour-clock land I’ve never seen it. I’ve seen it used in aviation when something is due to end at midnight. [Previous page](https://boards.straightdope.com/t/i-really-despise-the-12-00-am-deadline/503072.md?page=2)