childishness

/ˈtʃaɪldɪʃnəs/
noun
  1. Behavior or qualities that are silly, immature, or not appropriate for an adult.
    • The teacher was frustrated by the constant childishness in the classroom.
    • She outgrew her childishness and became a responsible young adult.
    • His childishness during the argument made everyone lose respect for him.
Antonyms
What does "childishness" mean? | whatsthatwordmean | whatsthatwordmean