Webster's 1913 Dictionary
IMMATURITY
Im `ma *tu "ri *ty, n. Etym: [L. immaturitas: cf. F. immaturité. ]
Defn: The state or quality of being immature or not fully developed; unripeness; incompleteness. When the world has outgrown its intellectual immaturity. Caird.
New American Oxford Dictionary
immaturity
im ma tu ri ty |ˌiməˈCHo͝oriti ɪməˈtʃʊrəti | ▶noun the state of being immature or not fully grown. • behavior that is appropriate to someone younger: they were shocked by such immaturity in a grown man.
Oxford Dictionary
immaturity
im |ma ¦tur |ity |ˌɪməˈtʃɔːrɪti, ˌɪməˈtʃʊərɪti, ˌɪməˈtjɔːrɪti, ˌɪməˈtjʊərɪti | ▶noun [ mass noun ] the state of being immature or not fully grown: the immaturity of the immune system in very young children makes them especially vulnerable. • behaviour that is appropriate to someone younger: they were shocked by such immaturity in a grown man.
Oxford Thesaurus
immaturity
immaturity noun 1 the immaturity of the fruit | the immaturity of the technology: unripeness, greenness, sourness; newness, rawness, crudeness, crudity, imperfection, incompleteness, lack of completion, lack of development. 2 they were shocked by such immaturity in a grown man: childishness, babyishness, infantilism, juvenility, puerility, lack of experience, inexperience, unworldliness, naivety, ingenuousness.
Sanseido Wisdom Dictionary
immaturity
im ma tu ri ty /ɪ̀mət j ú ə rəti /名詞 U 未熟, 未完成 ; 幼稚な態度 [行動 ].
The Wordsmith Dictionary