1. characteristic of a lack of maturity
- immature behavior
2. (used of living things especially persons) in an early period of life or development or growth
Similar word(s): immature, new, adolescent, teen, teenage, teenaged, infantile, boyish, boylike, schoolboyish, childlike, childly, early, girlish, schoolgirlish, junior, little, small, newborn, preadolescent, preteen, puppyish, puppylike, tender, youngish, vernal, young, youthful, junior, young
3. not fully developed or mature; not ripe
4. not yet mature
5. (of birds) not yet having developed feathers
Sentences with immature as an adjective:
- You're only young once, but you can be immature the rest of your life.
- The man was immature for throwing a tantrum.
1. An immature member of a species.