Dictionary.com
Thesaurus.com
Synonyms

immature

American  
[im-uh-choor, -toor, -tyoor, -chur] / ˈɪm əˈtʃʊər, -ˈtʊər, -ˈtjʊər, -ˈtʃɜr /

adjective

  1. not mature, ripe, developed, perfected, etc.

  2. emotionally undeveloped; juvenile; childish.

    Synonyms:
    babyish, puerile, callow
  3. Physical Geography. youthful.

  4. Archaic. premature.


immature British  
/ ˌɪməˈtjʊə, -ˈtʃʊə /

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms


Etymology

Origin of immature

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


Explanation

Use the adjective immature to describe something that is not fully grown: “Elizabeth rescued an immature sparrow that had fallen from its nest during the storm.” When used in a general sense, immature describes something in an early stage of development, such as an immature fruit tree or an immature political system. When applied to people, however, immature is often used to describe someone who behaves in a childish way. So if your 42-year-old brother spends the entire holiday weekend playing video games and then throws a temper tantrum when you ask him to help with the dishes, the word you’re looking for to describe him is probably immature.

Keep Reading on Vocabulary.com

Vocabulary lists containing immature

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Adolescents already have a harder time than adults with planning ahead and controlling their impulses, because of the brain’s immature prefrontal cortex.

From The Wall Street Journal ● Oct. 3, 2026

“While Scott responded to and made an immature comment on Snapchat, he did nothing else,” attorney Jeremy Saland wrote in an email to The Wall Street Journal.

From The Wall Street Journal ● Sep. 30, 2026

Sure, he’s obnoxious, immature, but he’s also now determined.

From Los Angeles Times ● Aug. 10, 2026

The immature insects are believed to spend between four and 10 years underground feeding on plant roots before emerging as adults.

From BBC ● Jul. 9, 2026

Jasmine lifts one eyebrow with a little smile, as if we just proved her boys are immature point before she turns off and heads down the hall with Camille and Breanna, toward the cafeteria.

From "King and the Dragonflies" by Kacen Callender

Random Word

Spin the wheel and learn a new word!

Get a word


Vocabulary.com logo
by dictionary.com

Just like flashcards, but way more fun

Don't take our word for it. Leave the boring studying behind and join VocabTrainer today. You'll learn even faster and never look back.

Take me to Vocabulary.com