lifespan
n. countable B2 Upper Intermediate US //ˈɫaɪfˌspæn// UK //lˈaɪfspæn// life·span
n. the length of time that a person, animal, or object is expected to live or last.
n. the duration of existence of an individual, organism, or object under normal conditions.
The average lifespan of a domestic cat is fifteen years.
Engineers are looking for ways to extend the lifespan of the bridge by using rust-resistant materials.
Advances in medical technology and improved sanitation have significantly increased the human lifespan over the last century, though regional disparities in healthcare access remain a critical concern.
From life + span.
Usage
Often used with adjectives like 'average', 'expected', or 'maximum'.