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

These seeds are expensive and unnecessary for sprouting, as sprouts are harvested when immature. — Kim Toscano, Southern Living, 14 Sep. 2026

The immature boy-king Richard II (Woody Norman) is racked with nightmares and unable to govern. — Bilge Ebiri, Vulture, 11 Sep. 2026

Top 5 most iconic college live mascot moments Reggie was an immature male and the zoo believed he was injured from a collision with a truck. — Maddie Rhodes, USA Today, 9 Sep. 2026

Harvesting too early on immature beds also affects the maturation of the rice kernels over time, officials said. — Frank Vaisvilas, jsonline.com, 9 Sep. 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