A Moment Was Once Ninety Seconds
A moment is a brief period. Medieval timekeeping gave it a precise length, and physics gave it a different meaning again.
A moment is a very brief period of time. Medieval reckoning made it exact: an hour was divided into forty moments, making a moment ninety seconds. Physics then took the word for something else entirely — a *moment* is a turning effect, from Latin *movimentum*, a movement, which is what the word originally meant.
- A brief period. *Wait a moment.*
- A particular point in time. *The moment of impact.*
- A turning effect (physics). *The moment of a force.*
- Importance. *A matter of some moment.*
Word forms
| Form | Word | Example |
|---|---|---|
| Noun | moment | A brief moment. |
| Plural | moments | Difficult moments. |
| Adjective | momentary | A momentary pause. |
| Adjective | momentous | A momentous decision. |
| Related | momentum | Gathering momentum. |
How it is used in a sentence
- A moment was once ninety seconds.A fortieth of an hour.
- Momentary and momentous differ.Brief versus important.
- The moment of a force turns an object.Physics.
Momentary, momentous, momentum
- Momentary — lasting a moment
- Momentous — of great importance
- Momentum — mass times velocity, and figuratively, impetus
- Moment of inertia — resistance to rotational acceleration
- All from movement — Latin *movimentum*
From Latin *momentum*, a movement or a moment of time, from *movere*, to move.
Momentary or momentous?
Momentary means lasting only a moment. Momentous means of great significance. They are easily confused and mean quite different things.
Was a moment really ninety seconds?
In medieval reckoning, yes. An hour was divided into forty moments, giving ninety seconds each.