mor·​tal·​i·​ty | \ mȯr-ˈta-lə-tē How to pronounce mortality (audio) \

Definition of mortality

1 : the quality or state of being mortal Her husband's death reminded her of her own mortality.
2 : the death of large numbers (as of people or animals) trying to reduce infant mortality
3 archaic : death
4 : the human race that natural extinction to which all mortality is subject— Thomas Paine
5a : the number of deaths in a given time or place The mortality among the infected mounted daily.
b : the proportion of deaths to population a brain infection with a mortality rate of about 30 percent— Jane E. Brody
c : the number lost or the rate of loss or failure the mortality rate of small businesses

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Thoughts on Mortality

Young people tend to assume they will never die, but a person's sense of his or her mortality generally increases year by year, and often increases greatly after a serious accident or illness. Still, many people refuse to change behaviors that would improve their chances of living into old age. Mortality rates are calculated by government agencies, insurance companies, and medical researchers. Infant mortality rates (the rate at which infants die in childbirth) provide a good indicator of a country's overall health; in recent years, the rates in countries like Iceland, Singapore, and Japan have been much better than in the U.S.

Examples of mortality in a Sentence

a leading cause of mortality

Recent Examples on the Web

Their buoyancy means their mortality rate is low, but the position of some of the ants suggests that these soldiers, like the demodogs, may die protecting their queen. Ashley Strickland, CNN, "The weird Upside Down science behind 'Stranger Things'," 4 July 2019 According to a study published in May, the elephant mortality rate from poaching is declining in response to lower demand for ivory on the international market, among other factors. Grant Currin, National Geographic, "Elderly male elephants are the most determined to mate," 2 July 2019 Germany had a high birth rate and a falling mortality rate. The Economist, "Why Germany’s birth rate is rising and Italy’s isn’t," 29 June 2019 But while no track is better equipped to handle a large event on short notice than is the home of the Kentucky Derby, Churchill’s recent mortality rates provide no shelter from harsh scrutiny. Tim Sullivan, The Courier-Journal, "Breeders' Cup taking a huge risk by racing at Santa Anita amid recent horse deaths," 27 June 2019 Since 1990, life expectancy has risen from 48 years to 66, and the mortality rate for children under 5 dropped from 152 per 1,000 live births to 42. Karl Vick, Time, "Is Rwanda's Paul Kagame a Strongman, a Technocrat, or Something in Between?," 27 June 2019 In fact, patients treated by burned out intensive care physicians have higher mortality rates. Quartz at Work, "Young female doctors are at high risk for burnout and “self-care” is not the answer," 27 June 2019 At age 45, the mortality rate from stroke is three times higher for blacks compared to whites. Jason Ashe, The Conversation, "Not all Americans have a fair path to a good death – racial disparities are real," 24 June 2019 Even if the goal is reached, Robinson said there will still be an inbred population, which could lead to a larger mortality rate. Andrew Nicla, azcentral, "Captive-born Mexican gray wolf pups released to 'foster dens' in Arizona and New Mexico," 23 June 2019

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

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First Known Use of mortality

15th century, in the meaning defined at sense 1

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Statistics for mortality

Last Updated

8 Jul 2019

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The first known use of mortality was in the 15th century

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English Language Learners Definition of mortality

: the quality or state of being a person or thing that is alive and therefore certain to die : the quality or state of being mortal
: the death of a person, animal, etc.
: the number of deaths that occur in a particular time or place


mor·​tal·​i·​ty | \ mȯr-ˈtal-ət-ē How to pronounce mortality (audio) \
plural mortalities

Medical Definition of mortality

1 : the quality or state of being mortal
2a : the number of deaths in a given time or place
b : the proportion of deaths to population : death rate

called also mortality rate

— compare fertility sense 2, morbidity sense 2

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Comments on mortality

What made you want to look up mortality? Please tell us where you read or heard it (including the quote, if possible).


an act or instance of editing or removing

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