# immature

/ˌɪmətˈjʊɹ/ (US) · /ˌɪmətʃˈɔː/ (UK)

Source: https://englishreference.com/word/immature
Updated: 2026-06-20

## Senses

### 1. childish behavior

adjective · CEFR B2

acting in a way that is silly or childish, especially for your age.

For teachers: exhibiting psychological or social behavior inappropriate for one's chronological age; puerile.

- It was very immature of him to start shouting just because he lost the game.
- The manager's immature response to constructive criticism created a toxic atmosphere within the department, as he often resorted to personal insults during meetings.

### 2. not fully grown

adjective · CEFR B2

not yet fully developed or grown.

For teachers: not having reached a state of full development or reproductive maturity.

- The immature birds still have gray feathers and cannot fly long distances yet.
- The biologist noted that the immature specimens lacked the distinctive markings found on adults of the same species.

### 3. happening too early

adjective · CEFR C2 · Archaic

happening before the right or expected time.

For teachers: occurring before the natural or proper time; premature.

- The poet wrote a sad poem about the immature death of a young soldier.
- In the nineteenth-century novel, the protagonist laments the immature end of his political career following the scandal.

### 4. a young animal

noun · CEFR C1 · Technical

an animal or plant that is not yet an adult.

For teachers: an individual organism that has not yet reached sexual maturity or its final adult form.

- The researchers counted twelve immatures among the group of seals on the beach.
- Distinguishing between immatures and females of this particular butterfly species requires careful examination of the wing patterns under a microscope.

## Examples

- His immature behavior at the party embarrassed his friends.
- The manager's immature reaction to criticism made it difficult for the team to provide honest feedback.
- While the biological markers of adulthood are clear, many psychologists argue that modern social structures allow individuals to remain emotionally immature well into their late twenties.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.