Comparison of male and female life expectancy at birth for countries and territories as defined in the 2018 CIA Factbook, with selected bubbles labelled. The green dotted line corresponds to equal female and male life expectancy. The apparent 3D volumes of the bubbles are linearly proportional to their population. (In the SVG file, hover over a bubble to highlight it and show its data.) The word<unk> " is sometimes used as a synonym for "life expectancy" in demography. However, the term<unk>  is sometimes meant to refer only to especially long-lived members of a population, whereas life expectancy is always defined statistically as the average number of years remaining at a given age. For example, a population's life expectancy at birth is the same as the average age at death for all people born in the same year (in the case of cohorts).<unk>  is best thought of as a term for general audiences meaning 'typical length of life' and specific statistical definitions should be clarified when necessary. Reflections on<unk>  have usually gone beyond acknowledging the brevity of human life and have included thinking about methods to extend life.<unk>  has been a topic not only for the scientific community but also for writers of travel, science fiction, and utopian novels. There are many difficulties in authenticating the longest human life span ever by modern verification standards, owing to inaccurate or incomplete birth statistics. Fiction, legend, and folklore have proposed or claimed life spans in the past or future vastly longer than those verified by modern standards, and<unk>  narratives and unverified<unk>  claims frequently speak of their existence in the present. A life annuity is a form of<unk>  insurance.
Longevity
Autism-friendly
Late-life mortality deceleration
Wellness 
Fall prevention
Reading disability
Worried well 
Social degeneration