Childish
Pronunciation : Child"ish
Part of Speech : a.
Definition : 1. Of, pertaining to, befitting, or resembling, a child. "Childish innocence." Macaulay.
2. Peurile; trifling; weak. Methinks that simplicity in her countenance is rather childish than innocent. Addison.
Note: Childish, as applied tc persons who are grown up, is in a disparaging sense; as, a childish temper.
Source : Webster's Unabridged Dictionary, 1913