immature

im·ma·ture

adjective \ˌi-mə-ˈtu̇r, -ˈtyu̇r, -ˈchu̇r\

: not fully developed or grown

: acting in a childish way : having or showing a lack of emotional maturity

Full Definition of IMMATURE

1

archaic :  premature

2

a :  lacking complete growth, differentiation, or development <immature fruits> <a sexually immature bird>

b :  having the potential capacity to attain a definitive form or state :  crude, unfinished <a vigorous but immature school of art>

c :  exhibiting less than an expected degree of maturity <emotionally immature adults>

— immature noun

— im·ma·ture·ly adverb

— im·ma·tu·ri·ty \-ˈtu̇r-ə-tē, -ˈtyu̇r-, -ˈchu̇r-\ noun

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Examples of IMMATURE

1. The flock included both adult and immature birds.
2. His teachers have complained about his immature behavior.

Origin of IMMATURE

Latin immaturus, from in- + maturus mature

First Known Use: 1548

Related to IMMATURE

Synonyms

adolescent, young, juvenile, youngish, youthful

Antonyms

adult, grown-up, mature, matured

Related Words

ephebic, minor, preteen, subadult, teenage (or teenaged), underage; embryonic, emergent; callow, green, inexperienced, puerile, raw; babyish, childish, childlike, infantile, infantine, kiddish; undeveloped, unfinished, unfledged, unformed, unripe, unripened; blooming, blossoming, burgeoning, flourishing, flowering

Near Antonyms

aged, aging (or ageing), ancient, elderly, geriatric, long-lived, old, older, oldish, senescent, senior; full-blown, full-fledged; golden, mellow, ripe, ripened; middle-aged; anile, decrepit, doddering, over-the-hill, senile, spavined, tottery

Rhymes with IMMATURE

amateur, aperture, armature, blackamoor, carrefour, carte du jour, coinsure, commissure, confiture, connoisseur, coverture, curvature, cynosure, embouchure, epicure, filature, forfeiture, garniture, geniture, green-manure, haute couture, insecure, ligature, manicure, overture, paramour, pedicure, plat du jour, portraiture, prelature, premature, quadrature, reassure, Reaumur, reinsure, saboteur, sepulture, sequitur, signature, simon-pure, sinecure, soup du jour, tablature, temperature, to be sure, troubadour, white amur, Yom Kippur

im·ma·ture

adjective \ˌim-ə-ˈt(y)u̇(ə)r also -ˈchu̇(ə)r\   (Medical Dictionary)

Medical Definition of IMMATURE

: lacking complete growth, differentiation, or development <immature blood cells> <emotionally immature>

—im·ma·ture·ly adverb

—im·ma·tu·ri·ty \-ˈt(y)u̇r-ət-ē also -ˈchu̇r-\ noun, plural im·ma·tu·ri·ties