senescence se·nes·cence (sĭ-něs'əns)
The process of growing old; aging.
senescent se·nes·cent (sĭ-něs'ənt)
Growing old; aging.
in human beings, the final stage of the normal life span. Definitions of old age are not consistent from the standpoints of biology, demography (conditions of mortality and morbidity), employment and retirement, and sociology. For statistical and public administrative purposes, however, old age is frequently defined as 60 or 65 years of age or older
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