Meanings

many years

tens of thousands of years

ayu

annual income threshold (that affects taxes or social insurance)

adolescence

one's increasing age

benchwarmer

middle class (kindergarten, pre-school, etc.)

year

next fiscal year

pension for the sick and wounded

rank-and-file employee who never gets promoted

biological age of the body (based on fitness metrics)

age range

shōnen manga

International Year of the Child

Uji Reform School

Kantouiryō Reform School

Kyōtoiryō Reform School

Miyagawairyō Reform School