Midday is twelve o'clock, the point where morning becomes afternoon and the abbreviations flip from am to pm. In Britain it is also the traditional time for the news bulletin, the moment the pips have marked for decades, and the deadline that turns up on more paperwork than any other — "by noon" is the standard wording for tenders, applications and auction closings.
School lunch sittings start around now, offices empty for an hour, and the term "lunchtime" covers anything from twelve to two depending on the trade. Sunday lunch bookings in pubs typically begin at midday and run until mid-afternoon.
Because twelve o'clock can be confusing in writing — 12 am and 12 pm are read differently by different people — a countdown expressed in hours and minutes removes the ambiguity entirely. This one targets the next midday, not midnight.
Common questions
Is midday the same as 12 pm?
Yes. Midday is twelve o'clock in the daytime, while midnight is the twelve at the start of the day.