Longevity
Part of speech: noun
Definition: The quality of being long-lasting, especially of life
Example sentence: Only 20 percent of our longevity is genetically determined. The rest is what we do, how we live our lives and increasingly the molecules that we take. It's not the loss of our DNA that causes aging, it's the problems in reading the information, the epigenetic noise.
Seniority
Part of speech: noun
Definition: A measure of the amount of time a person has been a member of an organization, as compared to other members, and with an eye towards awarding privileges to those who have been members longer.
Example sentence: I would feel more optimistic about a bright future for man if he spent less time proving that he can outwit Nature and more time tasting her sweetness and respecting her seniority.