behaviour that is not sensible and is typical of people who are much younger (行爲)不成熟的,不夠老練的,幼稚的 emotional immaturity 情感不成熟
the state of not being fully developed or grown 未長成的;發育未全的 the immaturity of renal function in some infants 一些嬰兒腎功能不全
opposite maturity