duration of service
"her longevity as a star"
"had unusual longevity in the company"
The quality of being long-lasting, especially of life.
"The secret to her remarkable longevity lies in a diet rich in vegetables and regular morning walks."
Longevity entered English in the early 17th century as a learned borrowing from Latin, where it meant "ancientness" or being aged. This word combines the root for "long" with a suffix meaning state or condition, which is why its pronunciation sometimes shifts to match the sound of the English word long.