mortality

noun

mor·​tal·​i·​ty mȯr-ˈta-lə-tē 

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

5

a

: the number of deaths in a population during a given time or place : the proportion of deaths to population : mortality rate

The mortality among the infected mounted daily.

b

: 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

Similarly, on paper, Klara and the Sun is a great idea, a way for adults to explain mortality to their kids while bracing themselves for redundancy. — Damon Wise, Deadline, 15 Oct. 2026

In 2025, the Earth passed its first climate tipping point, as rising ocean temperatures, acidification, overfishing, and pollution are combining to cause coral bleaching and mortality. — Simmone Shah, Time, 14 Oct. 2026

Acknowledging this — and reminding oneself daily of one’s mortality — is a core tenet of Buddhist teachings. — Maddie Connors, Los Angeles Times, 14 Oct. 2026

Douglas details his volatile relationship with his late father, Kirk Douglas, his son Cameron’s addiction and imprisonment and the Stage 4 cancer diagnosis that forced him to confront his own mortality. — Christina Dugan Ramirez, FOXNews.com, 10 Oct. 2026

Word History

Etymology

Middle English mortalite, borrowed from Anglo-French mortalité, mortelté, borrowed from Latin mortālitāt-, mortālitās, from mortālis "subject to death, mortal entry 1" + -itāt-, -itās -ity

First Known Use

15th century, in the meaning defined at sense 1

Phrases Containing mortality

• infant mortality
• mortality rate
• mortality table

Rhymes for mortality

• banality
• bestiality
• brutality
• carnality
• centrality
• chirality
• duality
• fatality
• finality
• formality
• frugality
• legality

Kids Definition

mortality

noun

mor·​tal·​i·​ty mȯr-ˈtal-ət-ē 

plural mortalities

1

: the quality or state of being mortal

2

: the death of large numbers (as of animals or people)

3

a

: the number of deaths in a given time or place

b

: the ratio of deaths occurring in a certain time in a given population to the number of individuals in the population

Medical Definition

mortality

noun

mor·​tal·​i·​ty mȯr-ˈtal-ət-ē 

plural mortalities

1

: the quality or state of being mortal

2

: the number of deaths in a population during a given time or place : the proportion of deaths to population : mortality rate compare morbidity sense 2