Writing tip #25: Frequently confused words - incident/incidence/instance

Misuse of the word ‘incidence’ is becoming so common that I think it’ll be one of those words that will change its meaning over time. But we’re not there yet, so I’ll take this moment to unravel the confusion.

An incident is an episode or an event. The incidence of something is the rate or extent of its occurrence. An instance is a case or example. For instance [that was deliberate, FYI], a car accident is an incident, whereas the incidence of car accidents refers to the rate or number of car accidents in a place and/or time. And if we’re talking about speed as a cause of car accidents, we might describe a particular car accident as an instance in which speed was a factor.

I recently read in an author’s note (in a published novel) that ‘all the incidences in this book really happened’. No! She meant ‘incidents’. Clearly the editor didn’t get to check the author’s note!