An event that is expected to happen very soon is known as?

The term "imminent" refers to an event that is likely to occur very soon or is impending. It conveys a sense of urgency and suggests that the event is not just anticipated but is expected to happen in the near future, often with a degree of inevitability. This is particularly relevant in contexts where timely action might be needed, such as in emergency situations.

The other terms, while related, do not carry the same urgency. "Upcoming" indicates something that is planned for the near future but does not specify how soon it will happen. "Immediate" refers to something that is occurring right now or requires instant attention, which may not align with events that are simply about to occur. "Scheduled" implies a planned or organized timeframe for an event, but it doesn't necessarily denote that the event is imminent or approaching swiftly. Thus, "imminent" most accurately describes an event that is expected to happen very soon.