act one's age

act one's age

Behave more maturely. Although the phrase often is used in asking children to act in a more grown-up fashion ( Only babies suck their thumbs; act your age), it also may refer to an adult who is, sometimes deliberately, acting much younger than might be considered appropriate ( Grandpa, it's time you stopped climbing ladders and acted your age).
See also: act, age
References in periodicals archive ?
The one good thing about really getting older, Travolta says, is being able to act one's age, or a little beyond.