soph·o·mor·ic 
/ˌsɑ:fˈmorɪk/ adjective
/ˌsɑ:fˈmorɪk/ adjective [more sophomoric; most sophomoric] US, disapproving : having or showing a lack of emotional maturity : foolish and immature
▪ a sophomoric joke ▪ His behavior at the party was sophomoric.
▪ a sophomoric joke ▪ His behavior at the party was sophomoric.
