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Synonyms

incidence

American  
[in-si-duhns] / ˈɪn sɪ dəns /

noun

  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.

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of incidence

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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Individuals who experienced only mild infections did not show this elevated risk and actually had a slight decrease in lung cancer incidence.

From Science Daily • Mar. 13, 2026

Liz Darlison, chief executive at Mesothelioma UK, said the country "shamefully has the highest incidence of mesothelioma in the world" with research urgently needed.

From BBC • Mar. 11, 2026

Caregiving incidence goes up to 31% among those with a parent who is 75 or older.

From MarketWatch • Feb. 26, 2026

The incidence of dementia among the elderly has fallen sharply in recent decades, several studies have found.

From The Wall Street Journal • Feb. 18, 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

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.