immaturity

UK: /ˌɪməˈtjʊərɪti/

US: (im′ə chŏŏr′i tē, -tŏŏr′-, -tyŏŏr′-, -chûr′-)

Inflections of 'immaturity' (n): npl: immaturities

WordReference Random House Unabridged Dictionary of American English © 2025

im•ma•tu•ri•ty  (im′ə chŏŏr′i tē, -tŏŏr′-, -tyŏŏr′-, -chûr′-), n., pl. -ties for 2.

1. a state or condition of being immature:
   the immaturity of one's behavior; the immaturity of a country's technology.
2. an immature action or attitude.

• immature + -ity, probably reflecting Latin immātūritās untimely haste, unripeness 1530–40

WordReference Random House Learner's Dictionary of American English © 2025

im•ma•ture /ˈɪməˈtʃʊr, -ˈtʊr/   adj. 

1. not mature or ripe:
   the immature seeds of a plant.
2. emotionally undeveloped;
   childish;
   juvenile:
   immature temper tantrums.

im•ma•ture•ly, adv.: 

acting immaturely and selfishly.

im•ma•tur•i•ty, n. [uncountable]

WordReference Random House Unabridged Dictionary of American English © 2025

im•ma•ture  (im′ə chŏŏr′, -tŏŏr′, -tyŏŏr′, -chûr′), adj. 

1. not mature, ripe, developed, perfected, etc.
2. emotionally undeveloped;
   juvenile;
   childish.
3. [Physical Geog.] youthful (def. 5).
4. [Archaic.] premature.

• Latin immātūrus unripe, hence, untimely. See im-², mature
• 1540–50

im′ma•ture′ly, adv. 
im′ma•ture′ness, n. 
Synonyms

• 2. callow, puerile, babyish.