(simile) Of a person, to age well; to look or become better as they become older.

Third-person singular simple present indicative form of age like a fine wine

(UK, Australia, New Zealand) present participle of age like a fine wine

present participle of age like milk

(idiomatic, usually imperative) Synonym of act one's age (“to behave in a mature manner; to avoid being childish”).

(US, Canada) present participle of age like a fine wine

(espionage) A spy who pretends to work for one side, when they are actually working for or passing information to the other.

One who or that which ages something. / (euphemistic) One who is aging; an elderly person.

The capacity, condition, or state of acting or of exerting power. / (sociology, philosophy, psychology) The capacity of individuals to act independently and to make their own free choices.

(grammar) A noun that denotes an agent that performs the action denoted by the verb from which the noun is derived, such as "rider" derived from "to ride", or "cutter" derived from "to cut".