A ‘moment’ is actually a specific amount of seconds

'I'll be back in a moment' is a thing we can often say if we don't plan be gone for too long.

It is often used off the cuff, and we don't think of an exact time we will be gone when we are using the word.

All these years though, it seems like we've been giving the people we are leaving for a short while an exact time of when we will be back.

However, we also can use 'I'll be back in a min' if we want to give a more precise time measurement. That's just common knowledge.

But that actually isn't the case, as some people were surprised that a moment actually refers to a specific amount of time.

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The word 'moment' actually means 90 seconds in time, so you do get another 30 seconds away from the people you don't like if you say, 'I'll be back in mo'.

The first reference of moment having this specific time attached to it comes from 1398 in none other than the Oxford English Dictionary.

Writer John of Trevisa said that there were 40 moments in an hour - making one moment 90 seconds.

However, Oxford has since replaced it 'a very brief period of time'.

The exact meaning of a moment as a unit of time comes from way back in medieval times, when a movement of a shadow on a sundial covered 40 moments in a solar hour.

The length of a solar hour depended on the day, which also varied from season to season.

In modern seconds, the length of a moment was never fixed, but on average, a moment would total 90 seconds.

A solar hour would be divided into 24 hours of equal or unequal lengths, with the hour divided into quarter-hours (4 puncti), 10 minuta, or 40 momenta.

The unit played an important role in medieval times until the introduction of the mechanical clock and the base 60 system in the late 13th century.

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Before then though, the unit was used medieval computists on a regular basis, as references to moment have been found as far back as the 8th century, with English monk Venerable Bede also known to use the system.

Despite that, it was not made to be used by people in everyday life, and we doubt that they had a saying for that back then.

In fact, the main marker for the passage of time for medieval commoners was a call to pray at intervals throughout the day.

Although, it's probably much easier to say 'I'll be back in a mo', rather than 'I'll be back in 90 seconds'.