life expectancy

average number of years a person can expect to live

Life expectancy is heavily dependent on the criteria used to select the group. In countries with high infant mortality rates, the life expectancy at birth is highly sensitive to the rate of death in the first few years of life. In these cases, another measure such as life expectancy at age 5 (e5) can be used to exclude the effects of infant mortality to reveal the effects of causes of death other than early childhood causes.
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Noun
1. an expected time to live as calculated on the basis of statistical probabilities
(hypernym) anticipation, expectancy

Expected further number of years of life measured at any age.

The length of time that an average person is expected to live, which is used by insurance companies to make projections of benefit payouts.