Definition of immature
- immature fruits
- a sexually immature bird
- emotionally immature adults
The flock included both adult and immature birds.
His teachers have complained about his immature behavior.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'immature.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
: not fully developed or grown
: acting in a childish way : having or showing a lack of emotional maturity
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