mortality rate

American  

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

noun

mortality rates plural

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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Other Word Forms

Noun Inflected Forms

• mortality rates
  plural

Etymology

Origin of mortality rate

First recorded in 1860–65

Example Sentences

By contrast, the measures the U.S. is taking to address this Ebola outbreak—with its high mortality rate and known transmission methods—are scientifically justified, sensitive to the epidemiological facts and specifically tailored to contain the outbreak.

From The Wall Street Journal • Jun. 3, 2026

The drug, called daraxonrasib, appears to be a breakthrough in managing a disease that has the highest mortality rate of all major cancers.

From BBC • Jun. 1, 2026

The incubation period is between two and 21 days, and the mortality rate in past Bundibugyo outbreaks was between 30% and 50%.

From MarketWatch • May 17, 2026

Faster chair stand performance was also linked to improved survival, with a 4% lower mortality rate for every 6-second improvement from the slowest to the fastest times.

From Science Daily • May 12, 2026

Now, thanks to the educational seminars and emergency care provided by the clinic’s volunteer staff, that mortality rate has been cut to less than one death per 30,000 trekkers.

From "Into Thin Air" by Jon Krakauer