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.
First Known Use: 1548See Words from the same year
: not fully developed or grown
: acting in a childish way : having or showing a lack of emotional maturity
What made you want to look up immature? Please tell us where you read or heard it (including the quote, if possible).
Merriam-Webster's New Words Quiz—Fall 2017 Edition!
Test your vocabulary with our 10-question quiz!TAKE THE QUIZ
Test Your Knowledge - and learn some interesting things along the way.TAKE THE QUIZ