Tell me more ×
English Language & Usage Stack Exchange is a question and answer site for linguists, etymologists, and serious English language enthusiasts. It's 100% free, no registration required.
up vote 3 down vote favorite

What do a.m. and p.m. stand for when talking about time?

share|improve this question
5  
I think this is easily answered by resources such as wikipedia. – JYelton Apr 5 '11 at 21:35

closed as off topic by Jeff Atwood♦ Apr 12 '11 at 7:03

Questions on English Language & Usage Stack Exchange are expected to relate to English language and usage within the scope defined in the FAQ. Consider editing the question or leaving comments for improvement if you believe the question can be reworded to fit within the scope. Read more about closed questions here.

1 Answer

up vote 11 down vote accepted

They are from the Latin for ante meridiem and post meridiem, which mean "before noon" and after noon", respectively.

share|improve this answer
5  
It is worth mentioning the crazy gotcha involving 12am and 12pm. 12pm means noon and 12:30pm is the half hour after noon. 12am means midnight. Many, many, many people get this incorrect. – MrHen Apr 5 '11 at 20:36
3  
@MrHen; The confusion is usually caused by the fact that 11am is directly followed by 12pm, or 12pm is directly followed by 1pm, rather than that 12:30pm follows 12:00pm. But otherwise you're correct, it's a common mistake. :) – roe Apr 5 '11 at 20:56
@all: Probably flirting with off-topicism here (I only got here from a link on Discussion re trivial questions), but I think MrHen's point could well be useful to a number of future 'seekers after knowledge' who might not have realised they were in danger of getting it wrong, and therefore might not have actively sought the additional info. In short, I don't see why OP should be rejected as 'trivial'. – FumbleFingers Apr 5 '11 at 23:41
Trying deperately to stay on-topic, I'll just say the standard rule is Midnight belongs to the new day, and woe betide any programmers, schedulers, etc. who get that wrong (but a surprising number do). – FumbleFingers Apr 5 '11 at 23:44
1  
If you're worried about confusion, you can just say 12 noon or 12 midnight. – Peter Shor Apr 6 '11 at 3:30
show 2 more comments

Not the answer you're looking for? Browse other questions tagged or ask your own question.