みせいじゅく 未成熟 LinksSentence search for 未成熟Sentence search for みせいじゅくKanji details for 未, 成 and 熟Edit in JMdict Noun, Noun which may take the genitive case particle 'no'1. immaturity; infancyAntonym: 成熟 Discussions Log in to talk about this word.