immature

adjective

im·​ma·​ture ˌi-mə-ˈchu̇r  -ˈtu̇r 

-ˈtyu̇r

1

a

: exhibiting less than an expected degree of maturity

emotionally immature adults

b

: lacking complete growth, differentiation, or development

immature fruits

a sexually immature bird

c

: having the potential capacity to attain a definitive form or state : crude, unfinished

immature talents

a vigorous but immature school of art

2

archaic : premature

immature noun

immaturely adverb

immaturity

ˌi-mə-ˈchu̇r-ə-tē 

-ˈtu̇r-, 

-ˈtyu̇r-

noun

Synonyms of immature

• young
• juvenile

Examples of immature in a Sentence

The flock included both adult and immature birds.

His teachers have complained about his immature behavior.

Recent Examples on the Web

The majority of the pest detections have been of immature life stages of the insect such as egg masses. — Lizzie Kane july 9, Sacbee.com, 9 July 2026

From the first whistle, the Americans looked too clumsy, disconnected and immature to compete for the World Cup quarterfinals berth. — Tom Krasovic, San Diego Union-Tribune, 8 July 2026

Digital twins are credible enough to be taken seriously by FTSE 100 marketing departments, but still immature enough that poor implementations will generate high-profile failures that set the capability back. — Cynthia Vega, Forbes.com, 7 July 2026

Look for eggplants that are smaller and immature, that are firm, smooth-skinned and heavy for their size — full-size and puffy ones can be bitter and have harder seeds. — Kate Bradshaw, Mercury News, 7 July 2026

Word History

Etymology

Latin immaturus, from in- + maturus mature

First Known Use

1548, in the meaning defined at sense 2

Rhymes for immature

• annexure
• embouchure
• epicure
• paramour
• premature
• reassure
• reinsure
• sinecure
• abjure
• adjure
• allure
• assure

Kids Definition

immature

adjective

im·​ma·​ture ˌim-ə-ˈt(y)u̇(ə)r 

1

: not mature or fully developed : young, unripe

an immature bird

immature fruit

2

: showing less than an expected degree of maturity

immature behavior

immaturely adverb

Medical Definition

immature

adjective

im·​ma·​ture

ˌim-ə-ˈt(y)u̇(ə)r also -ˈchu̇(ə)r

: lacking complete growth, differentiation, or development

immature blood cells

emotionally immature

immaturely adverb

immaturity

-ˈt(y)u̇r-ət-ē also -ˈchu̇r-

noun

plural immaturities