In Physics, an Event Is a Point in Space and Time
An event is something that happens. Relativity gives the word an exact meaning: a single location at a single moment.
An event is something that happens, or an organised occasion. Physics uses the word with unusual precision: an event is a single point in spacetime, specified by three space coordinates and one of time. The *event horizon* of a black hole is the boundary beyond which no event can ever be observed from outside. The Latin root *evenire* means to come out, so an event is literally an outcome — which is what *in the event of* still means.
- Something that happens. *A rare event.*
- An organised occasion. *A charity event.*
- A point in spacetime. *An event in relativity.*
- Event horizon — a black hole's boundary. *The event horizon.*
- Eventual — happening in the end. *Eventual success.*
Word forms
| Form | Word | Example |
|---|---|---|
| Noun | event | A big event. |
| Plural | events | Recent events. |
| Adjective | eventful | An eventful year. |
| Adjective | eventual | Eventual victory. |
| Latin | evenire | To come out. |
- The event sold out in an hour.Occasion.
- In the event of fire, use the stairs.Outcome sense.
- Nothing escapes an event horizon.Physics.
Event phrases
- In the event of — if this happens
- In any event — whatever happens
- Eventful — full of notable happenings
- Event horizon — the boundary of a black hole
- Non-event — something that fails to live up to expectation
Latin *eventus*, an occurrence or outcome, from *evenire*, to come out or result, from *ex-* plus *venire*, to come.
What is an event horizon?
The boundary around a black hole beyond which nothing, not even light, can escape to the outside.
Why does event mean outcome in some phrases?
Because the Latin root means to come out. In the event of preserves that older sense of result.