senectitude

noun

se·​nec·​ti·​tude si-ˈnek-tə-ˌtüd 

-ˌtyüd

: the final stage of the normal lifespan

Word History

Etymology

borrowed from Medieval Latin senectitūdin-, senectitūdō, re-formation, with Latin -tūdin-, -tūdō -tude, of Latin senectūt-, senectūs "old age," from senec-, variant stem of sen-, senex "old, aged" + -tūt-, -tūs, suffix of abstract nouns — more at senior entry 2

First Known Use

1796, in the meaning defined above