incidence

noun in·ci·dence \ ˈin(t)-sə-dən(t)s , -ˌden(t)s \

Updated on: 22 Apr 2018

Definition of incidence

1 a : angle of incidence

b : the arrival of something (such as a projectile or a ray of light) at a surface

2 a : an act or the fact or manner of falling upon or affecting : occurrence

b : rate of occurrence or influence

a high incidence of crime

See incidence defined for English-language learners

See incidence defined for kids

incidence was our Word of the Day on 10/09/2015. Hear the podcast!

Examples of incidence in a Sentence

an increased incidence of diabetes
a high incidence of criminal behavior

Recent Examples of incidence from the Web

To get around the sustainability issue overall, the report suggests that biotech companies focus on diseases or conditions that seem to be becoming more common and/or are already high-incidence.

— beth mole, Ars Technica, "“Is curing patients a sustainable business model?” Goldman Sachs analysts ask," 12 Apr. 2018
The Network Against Domestic Abuse has diligently worked to reduce the incidence of domestic violence providing assistance to adult victims and their children and through education to our youth in the schools.

— Courant Community, "Community News For The Enfield Edition," 10 Apr. 2018
Using data from 5300 premature babies in the NICU at Brigham and Women's Hospital in Boston, Puopolo showed that those born via C-section had one-twelfth the incidence of sepsis.

— marla broadfoot, Science | AAAS, "Too many antibiotics can give preemies a lifetime of ill health," 5 Apr. 2018
The tennis player must raise the hamstring's fatigue threshold, due to the higher incidence of deceleration experienced on a clay surface and overwork by the quadriceps.

— NOLA.com, "Optimum Performance: Serena Williams' clay court path to the French Open," 30 Mar. 2018
Tracking of benign brain tumors, such as acoustic neuromas, was initiated in 2004 by investigators at the institute’s Surveillance, Epidemiology and End Results program, which monitors and publishes statistics on cancer incidence rates.

— charles schmidt, Scientific American, "New Studies Link Cell Phone Radiation with Cancer," 29 Mar. 2018
Here's a sobering fact: Since the 1980s, incidences of melanoma, the deadliest form of skin cancer, have doubled.

— elizabeth siegel, Allure, "Why Skin Cancer Is the Most Common Type of Cancer — and Why Women Are More Likely to Contract It," 21 Mar. 2018
In a follow-up trial, results of which were published in 2011, patients given the drug had nearly half the incidence of AF as those not receiving it.

— clifton leaf, Fortune, "Brainstorm Health: Clinical Trials, Health Care Startup for the Poor, The Cost of CHIP," 6 Jan. 2018
Toothpaste is another matter, and Hammock points out that the concentration of triclosan is low in Colgate Total, while, at the same time, the incidence of gingivitis is high enough to warrant the compound’s inclusion.

— alexander nazaryan, Newsweek, "Is Cancer Lurking in Your Toothpaste? (And Your Soap? And Your Lipstick?)," 4 Sep. 2014

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'incidence.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Did You Know?

The words incident, incidence, and instance may seem similar (and, in fact, incident and incidence are closely related), but they are not used identically. In current use, incidence usually means "rate of occurrence" and is often qualified in some way ("a high incidence of diabetes"). Incident usually refers to a particular event, often something unusual or unpleasant ("many such incidents go unreported"). Instance suggests a particular occurrence that is offered as an example ("another instance of bureaucratic bumbling"); it can also be synonymous with case ("many instances in which the wrong form was submitted"). The plural incidences sometimes occurs in such contexts as "several recent incidences of crime," but this use is often criticized as incorrect.

First Known Use of incidence

1626

INCIDENCE Defined for English Language Learners

incidence

noun

Definition of incidence for English Language Learners

: the number of times something happens or develops : the rate at which something occurs
: the angle at which a ray (such as a ray of light) hits a surface

Medical Dictionary

incidence

noun in·ci·dence \ ˈin(t)-səd-ən(t)s, -sə-ˌden(t)s \

medical Definition of incidence

1 a : angle of incidence

b : the arrival of something (as a ray of light) at a surface

2 a : an act or the fact or manner of occurring or affecting

diseases of domestic incidence
—Science

b : rate of occurrence or influence; especially : the rate of occurrence of new cases of a particular disease in a population being studied — compare prevalence

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Spanish Central: Translation of incidence Nglish: Translation of incidence for Spanish speakers Britannica English: Translation of incidence for Arabic speakers

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incidence

Definition of incidence

incidence was our Word of the Day on 10/09/2015. Hear the podcast!

Examples of incidence in a Sentence

Recent Examples of incidence from the Web

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First Known Use of incidence

INCIDENCE Defined for English Language Learners

incidence

Definition of incidence for English Language Learners

Medical Dictionary

incidence

medical Definition of incidence

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Definition of incidence

incidence was our Word of the Day on 10/09/2015. Hear the podcast!

Examples of incidence in a Sentence

Recent Examples of incidence from the Web

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First Known Use of incidence

INCIDENCE Defined for English Language Learners

incidence

Definition of incidence for English Language Learners

Medical Dictionary

incidence

medical Definition of incidence

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