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

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Etymology

Origin of incidence

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

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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

When the researchers compared tea drinking habits with the incidence of these diseases, they found that regular tea consumption was associated with an 11% lower risk of the combined vascular outcomes.

From Science Daily ● Nov. 1, 2026

“We’re seeing that there’s a continued rise in the incidence of cancer across multiple different patient segments,” GSK’s Abdullah said.

From The Wall Street Journal ● Oct. 27, 2026

Iowa’s overall cancer incidence roughly tracked the U.S. average from 2000 to 2013, but rates have since risen in Iowa while declining nationwide.

From The Wall Street Journal ● Oct. 21, 2026

However, bowel and ovarian cancers stood out because their incidence rose significantly among younger adults but not among older people.

From Science Daily ● Oct. 14, 2026

There is a possible problem, however, since the index doesn’t clearly distinguish incidence from likelihood.

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

Morgan’s Celine Pannuti had said that a strong flu season could uplift sales for Haleon, with rising incidences in Europe and the U.S.

From The Wall Street Journal ● Oct. 29, 2026

According to available data, around twenty incidences were reported in the maritime area along the French Riviera between the 16th century and the early 2000s with waves often exceeding two meters.

From Science Daily ● May 21, 2026

Many have been on higher alert in recent years as incidences of antisemitism increase across the country.

From BBC ● Mar. 12, 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

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

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Related Words

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

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