Nanosecond
A nanosecond is far too short to do anything in, so nobody has ever been late within one.
Lunchtime
Lunchtime is the time of day when it is time for lunch, which begins roughly forty minutes before it officially does.
Dusk
There are three official dusks, each a bit darker than the last, and each defined by a different committee.
Decade
A decade is ten years, although nobody can agree which ten, least of all the decade itself.
Elevenses
Moving elevenses to ten o’clock produces tenses, which grammarians do not allow.
Evening
Evening is the part of the day after the afternoon has gone and before night has worked up the nerve.
Nap
A nap is a sleep that has been told to be back by four, and almost never is.
Year of Confusion
The year 46 BC lasted 445 days, as the Romans added extra months to fix their calendar.
Time zone
Nepal’s time is 5 hours 45 minutes ahead of UTC, and France covers 12 time zones.
Leap second
Since 1972, 27 leap seconds have been added to clocks, briefly making the time 23:59:60.