immature

[ im-uh-choor, -toor, -tyoor, -chur ]

adjective

1. not mature, ripe, developed, perfected, etc.
2. emotionally undeveloped; juvenile; childish.

   Synonyms: babyish, puerile, callow

3. Physical Geography. youthful ( def 5 ).
4. Archaic. premature.

immature

/ -ˈtʃʊə; ˌɪməˈtjʊə /

adjective

1. not fully grown or developed
2. deficient in maturity; lacking wisdom, insight, emotional stability, etc
3. geography a less common term for youthful

Derived Forms

• ˌimmaˈturity, noun
• ˌimmaˈturely, adverb

Other Words From

• imma·turely adverb
• imma·tureness noun

Word History and Origins

Origin of immature¹

First recorded in 1540–50, immature is from the Latin word immātūrus unripe, hence, untimely. See im- ², mature

Example Sentences

Mature eggs could be fertilized immediately after acquisition, while immature eggs needed to be matured before fertilization.

From Science Daily

Mark Heywood KC, defending Alesbrook, said the defendant was "very young and very immature" at the time of the offences, but was "capable of being a very caring father figure".

From BBC

When her friend asks her to underage drink under a bridge, she begrudges teenagers to Paul because "they all act so immature."

From Salon

Because people are immature and they get upset about things!

From Los Angeles Times

She also taught the pupil, and said that there had been some problems with behaviour, saying she could be “immature” and “either really happy or moody”.

From BBC

Related Words

• childish
• premature