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

So far, no conclusive evidence shows that naps themselves lead directly to an increase in mortality, according to Walia. —Brian Mastroianni, Health, 19 June 2025

While there has been a 34% decline in cancer mortality since 1991, primarily attributed to earlier detection and preventative health practices, Knudsen's new role places her at the forefront of efforts to fund a new generation of breakthrough cancer drugs. —Afshan Musani, CNBC, 18 June 2025

However, severe, inflexible deformities that need aggressive bony carpentry to correct the spine’s alignment carry complication rates up to 60%, with major deformity surgeries posing a 1% mortality risk within a year. —Richard Menger Md Mpa, Forbes.com, 17 June 2025

Randomized trials powered to demonstrate reductions in cancer-specific mortality can take decades. —Siddhartha Mukherjee, New Yorker, 16 June 2025

Word History

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