im·ma·ture (ĭm′ə-tyr, -chr, -tr)
1. Not fully grown or developed: an immature plant.
2. Marked by or suggesting a lack of normal maturity: silly, immature behavior. See Synonyms at young.
An immature animal; a juvenile.
[Latin immātūrus : in-, not; see IN-1 + mātūrus, mature; see mā-1 in the Appendix of Indo-European roots.]
im′ma·turi·ty, im′ma·tureness n.
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.