[time-nuts] am, m, pm and ?

David Kirkby david.kirkby at onetel.net
Mon Jul 18 01:49:33 EDT 2005

Dave Carlson wrote:
> This is something that I've wondered about. I know that someone out there
> will know or at least have an opinion.
> It's generally agreed that time between midnight and noon is expressed as
> hh:mm:ss with the "am" suffix for "ante meridian" (yes, I'm keeping this
> discussion to a 12-hour clock). Also of course that times from noon to
> midnight are expressed as hh:mm:ss with the "pm" suffix for "post meridian".
> Also I've heard that noon is known as meridian or "m" and that the time
> 12:00:00 exactly could have the "m" suffix, even if this time only exists
> for a brief moment, loosely speaking.
> What I'm wondering is what do we call midnight, given these conventions? The
> time 00:00:00 is not really pm or am, as are 11:59:59 pm and 00:00:01 am
> are. Somehow saying 12:00:00 am sounds inconsistent. Is there perhaps some
> archaic suffix that was or is used to denote exact midnight, just as "m" is
> used to denote exact noon?
> Dave Carlson

This once sparked a long discussion when the system administrator at 
work said he was going to shut down the computer system at 12 AM (or 
perhaps he said PM). Anyway, whatever one of the two it was, some 
thought his usage incorrect, so there were about 5 emails around on the 
subject. From what I gathered there, it is not used consistantly 
throughout the world by the general public, with some countries 
considering noon 12am, and others 12pm.

David Kirkby,

Please check out http://www.g8wrb.org/
of if you live in Essex http://www.southminster-branch-line.org.uk/

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