Synonyms:
adolescent, jejune, juvenile, puerile
Meaning: displaying or suggesting a lack of maturity; "adolescent insecurity"; "jejune responses to our problems"; "their behavior was juvenile"; "puerile jokes"
Synonyms:
puerile
Meaning: of or characteristic of a child; "puerile breathing"
Usage examples
For pity's sake, why was it that he was impelled to such a puerile weakness--such a vanity, as he sternly called it.
These scraps of puerile pedantry would indeed matter little if it were not also true that the alleged philosophical resemblances are also of these two kinds, either proving too much or not proving anything.