mortality rate

noun

plural mortality rates

: the ratio between deaths and individuals in a specified population and during a particular time period : the incidence of deaths in a given population during a defined time period (such as one year) that is typically expressed per 1000 or 100,000 individuals : death rate

an annual mortality rate of 15 deaths per 1000 people

Note: A crude mortality rate does not distinguish between specific causes of death or groups of individuals and measures the incidence of all deaths in a population during a given time period. More specific mortality rates are based on narrower categories of individuals or causes of death.

an infant mortality rate of 9 deaths per 1000 live births

mortality rates of lung cancer patients

infectious disease mortality rates

Examples of mortality rate in a Sentence

Recent Examples on the Web

Massachusetts was ranked first for its low infant-mortality rate and low maternal-mortality rate. — Tania Azhang, Sacbee.com, 11 Aug. 2026

Motor vehicle deaths also rose for middle-aged people in Colorado, but a larger increase in overdoses was the top factor keeping their mortality rates up. — Meg Wingerter, Denver Post, 9 Aug. 2026

If there is a glimmer of hope in the smoke, it can be found in the relatively low mortality rates for these recent urban fires, and their largely successful evacuations, which demonstrate real social cohesion and admirable courage and civic spirit. — John Vaillant, Time, 8 Aug. 2026

The mortality rate is unknown, though some studies suggest a range of roughly 30% to over 60%. — Mary Walrath-Holdridge, USA Today, 6 Aug. 2026

Word History

First Known Use

1855, in the meaning defined above

Rhymes for mortality rate

• borosilicate
• decontaminate
• deoxycholate
• deteriorate
• differentiate
• diisocyanate
• dinoflagellate
• excommunicate
• incapacitate
• insubordinate
• intercorporate
• interpenetrate

Medical Definition

mortality rate

noun

: the ratio between deaths and individuals in a specified population and during a particular time period : the incidence of deaths in a given population during a defined time period (such as one year) that is typically expressed per 1000 or 100,000 individuals : death rate

an annual mortality rate of 15 deaths per 1000 people

Note: A crude mortality rate does not distinguish between specific causes of death or groups of individuals and measures the incidence of all deaths in a population during a given time period. More specific mortality rates are based on narrower categories of individuals or causes of death.

mortality rates of liver cancer patients

an infant mortality rate of 9 deaths per 1000 live births