incidence

American  

[in-si-duhns] / ˈɪn sɪ dəns /

noun

• incidences
  plural

1. the rate or range of occurrence or influence of something, especially of something unwanted.

   the high incidence of heart disease in men over 40.

2. a falling upon, affecting, or befalling; occurrence.

   The incidence of murder that Sunday afternoon shocked the sleepy village.

3. Optics, Physics.

   1. the striking of a ray of light, beam of electrons, etc., on a surface, or the direction of striking.

   2. angle of incidence.

4. the fact or the manner of being incident.

5. Geometry. partial coincidence of two figures, as of a line and a plane containing it.

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incidence British  

/ ˈɪnsɪdəns /

noun

1. degree, extent, or frequency of occurrence; amount

   a high incidence of death from pneumonia

2. the act or manner of impinging on or affecting by proximity or influence

3. physics the arrival of a beam of light or particles at a surface See also angle of incidence

4. geometry the partial coincidence of two configurations, such as a point that lies on a circle

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Other Word Forms

Noun Inflected Forms

• incidences
  plural

Etymology

Origin of incidence

First recorded in 1375–1425; late Middle English, from Late Latin incidentia. See incident, -ence

Explanation

Incidence means the frequency with which something bad occurs. You’ll hear of “incidences of cancer” or “incidences of war." You hope the incidence is decreasing, not increasing. You might confuse incidence and incident. They sound similar, but incident refers only to something that happened, not to the frequency with which it happens. After a car accident, the police file an incident report, which is a fancy way of saying they write down what happened. Looking at these reports grouped together can show you if the incidence of accidents at specific intersections in town is on the rise.

Example Sentences

See Examples For:

incidence incidences

Hispanic women have a 40 percent higher incidence of cervical cancer and 20 percent higher death rate from it compared to non-Hispanic white women.

From Slate ● Sep. 17, 2026

Researchers have found first responders and other workers at the World Trade Center site have a higher incidence of leukemia than the general population.

From The Wall Street Journal ● Sep. 11, 2026

"The changes that are being talked about are not going to mean that every incidence of bad behaviour is going to suddenly change the way that finances are resolved," she said.

From BBC ● Sep. 9, 2026

Cancer incidence rates differed by roughly four to five times across regions.

From Science Daily ● Sep. 7, 2026

In fact, any health practice, such as milk drinking, which correlates positively with longevity will probably do the same with cancer incidence.

From "Innumeracy: Mathematical Illiteracy and Its Consequences" by John Allen Paulos

Local rail has also seen a rise in incidences, such as delays, cancellations and technical problems, which have more than tripled since 2019 on the Madrid local Cercanías network.

From BBC ● Jan. 23, 2026

One example featured a patient hospitalized for gout who told viewers that they "can reduce your incidences of gout if you cut back on your salt, your alcohol, and your red meat."

From Science Daily ● Jan. 9, 2026

Their incidences, however, grew significantly worse in wartime, especially among civilians who didn’t have the same access to doctors and medical hospitals as armed groups.

From Salon ● Jul. 20, 2025

The DOC responds to around 85 incidences a year on average, mostly consisting of single animals.

From BBC ● Nov. 25, 2024

Inaccurate data from countries with high incidences of MDR have made it difficult for pharmaceutical companies to meet demand for these drugs consistently, and therefore market prices have fluctuated.

From "Mountains Beyond Mountains" by Tracy Kidder and Michael French

Related Words

• extent
• frequency
• percentage
• prevalence
• proportion
• rate