act one's age

Stop being childish

To act one's age is to behave with the maturity expected of someone your years—usually said as a rebuke to adults acting childishly: Act your age, not your shoe size.

The phrase implies that age brings certain behavioral standards, and failing to meet them is embarrassing or inappropriate.

Occasionally used with children who are being babyish for their developmental stage.

Related

decorum · adolescence · life stages · grow up · aging · emotional regulation · temper tantrum · milestones · societal roles · self-awareness · childishness · propriety · social expectations · immaturity · patience · prudence · respectability · accountability

Opposites
maturity of behavior

act one's agehorse around

Play boisterously and roughly

clown around · goof off · act the fool · fool around · regress

social conformity

act one's agemake a spectacle of oneself

Act embarrassingly in public

Family

act, acts, acted, acting, action, actions, active, actor, actors

Familiarity
Top 100,000
Profile
Known to kids · Used worldwide · Timeless · Abstract · Everyday, not technical · Rated G