in·fan·tile (ĭnfən-tīl′, -tĭl)
1. Of or relating to infants or infancy.
2. Displaying or suggesting a lack of maturity; childish: infantile behavior; an infantile remark. See Synonyms at young.
[Middle English infantil, from Latin īnfantīlis, from īnfāns, īnfant-, infant; see INFANT.]
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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.