Definition of years younginformal
- She's 60 years young today!
: the period of about 3651/4 solar days required for one revolution of the earth around the sun
: the time required for the apparent sun to return to an arbitrary fixed or moving reference point in the sky
: the time in which a planet completes a revolution about the sun
: being in the first or an early stage of life, growth, or development
: of an early, tender, or desirable age for use as food or drink
: young persons : youth
: immature offspring
: a single recently born or hatched animal
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