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

“Even though it’s much more rare, the mortality rate for men is 19% higher for breast cancer than for women,” says Ambrose.

From Los Angeles Times • Mar. 17, 2026

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

From The Wall Street Journal • Feb. 24, 2026

Studies show that ʻiʻiwi, also known as the scarlet honeycreeper, face a mortality rate of about 90 percent if infected.

From Science Daily • Feb. 11, 2026

And this follows Ukraine's population declining between 1992 and 2022, from 52 million to 41 million, due to a high mortality rate, migration and a decline in birth rates.

From BBC • Jan. 9, 2026

But that changed when the federal government ordered the hospitals to be desegregated: within just seven years, the black infant mortality rate had been cut in half.

From "Freakonomics: A Rogue Economist Explores the Hidden Side of Everything" by Steven D. Levitt