1. resembling or characteristic of an adult; mature in behavior or appearance

Examples

• The ten-year-old showed adultlike responsibility when caring for her younger siblings.
• His adultlike reasoning impressed the teachers during the debate.
• She had an adultlike understanding of the family’s financial situation.
• The child’s adultlike behavior at the formal dinner surprised everyone.
• His adultlike appearance made him seem older than his actual age.
• The teenager displayed adultlike maturity when handling the crisis.