mortality rate

American  

[mawr-tal-i-tee reyt] / mɔrˈtæl ɪ ti ˌreɪt /

noun

1. the relative frequency of deaths in a specific population during a specified time, often cited as the percentage of human deaths during a public health crisis, or of wildlife deaths due to environmental perils.

   Patients over the age of 80 had the highest mortality rate during the last flu season.

   The mortality rate of the bald eagle falls to about 25 percent after the first year of life.

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mortality rate British  

noun

1. another term for death rate

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Etymology

Origin of mortality rate

First recorded in 1860–65

Example Sentences

Although the facility was meant to care for the dying, its patient mortality rate was about 2.3% during the last five years, according to the Centers for Medicare and Medicaid Services, or CMS.

From Los Angeles Times • Apr. 2, 2026

After analyzing health records, the team found that people who had both bladder cancer and colorblindness faced a 52% higher mortality rate over 20 years compared with bladder cancer patients who have normal vision.

From Science Daily • Mar. 10, 2026

The infant mortality rate is three times higher than in Denmark.

From The Wall Street Journal • Feb. 24, 2026

China also recorded 11.31 million deaths in 2025, a mortality rate of 8.04 per thousand -- leading to a population decline of 2.41 per thousand, NBS data showed.

From Barron's • Jan. 19, 2026

When lice were collected and tested, it was found that 5 per cent DDT powder caused no increase in their natural mortality rate.

From "Silent Spring" by Rachel Carson