1 usually prenominal. a coming after the eleventh in number or counting order, position, time, etc.; being the ordinal number of twelve: often written 12th.

What does it mean by the 12th hour?

The latest possible time, as in We turned in our report at the eleventh hour. This term is thought to allude to the parable of the laborers (Matthew 20:1–16), in which those workers hired at the eleventh hour of a twelve-hour working day were paid the same amount as those who began in the first hour. [ Early 1800s]

What does the at the eleventh hour mean?

: the latest possible time before it is too late still making changes at the eleventh hour.