noun
(countable) The amount of time that some being has been alive, or that some thing has been in existence, as measured from its birth or origin until the present or until some other given reference point. (Often measured in number of years; alternatively in months, days, hours, etc.; see also the usage notes)
(uncountable) The state of being old; the latter part of life.
(countable) Any particular stage of life.
(countable) The time of life at which some particular power or capacity is understood to become vested.
(uncountable) Maturity; especially, the time of life at which one attains full personal rights and capacities.
(countable) A particular period of time in history, as distinguished from others.
(astrology) One of the twelve divisions of a Great Year, equal to roughly 2000 years and governed by one of the zodiacal signs; a Platonic month.
(countable) A period of one hundred years; a century.
(countable, uncommon, possibly dated) A generation.
(countable, hyperbolic) A long time.
(countable) Lifespan, lifetime; the total time that some being is alive from birth to death (or some category of beings, on average).
(countable, poker) The entitlement of the player to the left of the dealer to pass the first round in betting, and then to come in last or stay out; also, the player holding this position; the eldest hand.
verb
(intransitive) To grow aged; to become old or older; to show marks of age.
(transitive) To cause to grow old; to impart the characteristics of age to.
(transitive) To determine the age of (the length of time that something has been alive or in existence).
(transitive) To indicate or reveal that (a person) has been alive for a certain period of time, especially a long one.
(transitive, figuratively) To allow (something) to persist by postponing an action that would extinguish it, as a debt.
(transitive, accounting) To categorize by age.